Science.gov

Sample records for americanus induces neutralizing

  1. An enzymatically inactivated hemoglobinase from Necator americanus induces neutralizing antibodies against multiple hookworm species and protects dogs against heterologous hookworm infection.

    PubMed

    Pearson, Mark S; Bethony, Jeffrey M; Pickering, Darren A; de Oliveira, Luciana M; Jariwala, Amar; Santiago, Helton; Miles, Aaron P; Zhan, Bin; Jiang, Desheng; Ranjit, Najju; Mulvenna, Jason; Tribolet, Leon; Plieskatt, Jordan; Smith, Tracey; Bottazzi, Maria Elena; Jones, Kathryn; Keegan, Brian; Hotez, Peter J; Loukas, Alex

    2009-09-01

    Hookworms digest hemoglobin from erythrocytes via a proteolytic cascade that begins with the aspartic protease, APR-1. Ac-APR-1 from the dog hookworm, Ancylostoma caninum, protects dogs against hookworm infection via antibodies that neutralize enzymatic activity and interrupt blood-feeding. Toward developing a human hookworm vaccine, we expressed both wild-type (Na-APR-1(wt)) and mutant (Na-APR-1(mut)-mutagenesis of the catalytic aspartic acids) forms of Na-APR-1 from the human hookworm, Necator americanus. Refolded Na-APR-1(wt) was catalytically active, and Na-APR-1(mut) was catalytically inactive but still bound substrates. Vaccination of canines with Na-APR-1(mut) and heterologous challenge with A. caninum resulted in significantly reduced parasite egg burdens (P=0.034) and weight loss (P=0.022). Vaccinated dogs also had less gut pathology, fewer adult worms, and reduced blood loss compared to controls but these did not reach statistical significance. Vaccination with Na-APR-1(mut) induced antibodies that bound the native enzyme in the parasite gut and neutralized enzymatic activity of Na-APR-1(wt) and APR-1 orthologues from three other hookworm species that infect humans. IgG1 against Na-APR-1(mut) was the most prominently detected antibody in sera from people resident in high-transmission areas for N. americanus, indicating that natural boosting may occur in exposed humans. Na-APR-1(mut) is now a lead antigen for the development of an antihematophagy vaccine for human hookworm disease.

  2. Assessment of Dredge-induced Sedimentation Effects on Winter Flounder (pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  3. Assessment of Dredging-Induced Sedimentation Effects on Winter Flounder (Pseudopleuronectes americanus) Hatching Success: Results of Laboratory Investigations

    EPA Science Inventory

    Historically of significant commercial and recreational value, winter flounder (Pseudopleuronectes americanus) stocks have declined steadily over the last 20 years and are currently at an all-time low. Although overfishing and climate change have been implicated, habitat alterat...

  4. Candidatus Liberibacter americanus induces significant reprogramming of the transcriptome of the susceptible citrus genotype

    PubMed Central

    2013-01-01

    Background Citrus huanglongbing (HLB) disease is caused by endogenous, phloem-restricted, Gram negative, uncultured bacteria named Candidatus Liberibacter africanus (CaLaf), Ca. L. asiaticus (CaLas), and Ca. L. americanus (CaLam), depending on the continent where the bacteria were first detected. The Asian citrus psyllid vector, Diaphorina citri, transmits CaLas and CaLam and both Liberibacter species are present in Brazil. Several studies of the transcriptional response of citrus plants manifesting HLB symptoms have been reported, but only for CaLas infection. This study evaluated the transcriptional reprogramming of a susceptible genotype of sweet orange challenged with CaLam, using a customized 385K microarray containing approximately 32,000 unigene transcripts. We analyzed global changes in gene expression of CaLam-infected leaves of sweet orange during the symptomatic stage of infection and compared the results with previously published microarray studies that used CaLas-infected plants. Twenty candidate genes were selected to validate the expression profiles in symptomatic and asymptomatic PCR-positive leaves infected with CaLas or CaLam. Results The microarray analysis identified 633 differentially expressed genes during the symptomatic stage of CaLam infection. Among them, 418 (66%) were upregulated and 215 (34%) were down regulated. Five hundred and fourteen genes (81%) were orthologs of genes from Arabidopsis thaliana. Gene set enrichment analysis (GSEA) revealed that several of the transcripts encoded transporters associated with the endomembrane system, especially zinc transport. Among the most biologically relevant gene transcripts in GSEA were those related to signaling, metabolism and/or stimulus to hormones, genes responding to stress and pathogenesis, biosynthesis of secondary metabolites, oxidative stress and transcription factors belonging to different families. Real time PCR of 20 candidate genes validated the expression pattern of some genes in

  5. Eastern equine encephalitis in moose (Alces americanus) in northeastern Vermont.

    PubMed

    Mutebi, John-Paul; Swope, Bethany N; Saxton-Shaw, Kali D; Graham, Alan C; Turmel, Jon P; Berl, Erica

    2012-10-01

    During fall 2010, 21 moose (Alces americanus) sera collected in northeastern Vermont were screened for eastern equine encephalitis virus (EEEV) antibodies using plaque reduction neutralization tests. Six (29%) were antibody positive. This is the first evidence of EEEV activity in Vermont, and the second report of EEEV antibodies in moose.

  6. The Relationship between Neutralization Techniques and Induced Abortion

    PubMed Central

    Kalateh Sadati, Ahmad; Tabei, Seyed Ziaaddin; Salehzadeh, Hamzeh; Rahnavard, Farnaz; Namavar Jahromi, Bahia; Hemmati, Soroor

    2014-01-01

    Background: Induced abortion is not only a serious threat for women’s health, but also a controversial topic for its ethical and moral problems. We aimed to evaluate the relationship between neutralization techniques and attempting to commit abortion in married women with unintended pregnancy. Methods: After in-depth interviews with some women who had attempted abortion, neutralization themes were gathered. Next, to analyze the data quantitatively, a questionnaire was created including demographic and psychosocial variables specifically related to neutralization. The participants were divided into two groups (abortion and control) of unintended pregnancy and were then compared. Results: Analysis of psychosocial variables revealed a significant difference in the two groups at neutralization, showing that neutralization in the control group (56.97±10.24) was higher than that in the abortion group (44.19±12.44). To evaluate the findings more accurately, we examined the causal factors behind the behaviors of the abortion group. Binary logistic regression showed that among psychosocial factors, neutralization significantly affected abortion (95% CI=1.07-1.35). Conclusion: Despite the network of many factors affecting induced abortion, neutralization plays an important role in reinforcing the tendency to attempt abortion. Furthermore, the decline of religious beliefs, as a result of the secular context of the modern world, seems to have an important role in neutralizing induced abortion. PMID:25349851

  7. HIV Neutralizing Antibodies Induced by Native-like Envelope Trimers

    PubMed Central

    Sanders, Rogier W.; van Gils, Marit J.; Derking, Ronald; Sok, Devin; Ketas, Thomas J.; Burger, Judith A.; Ozorowski, Gabriel; Cupo, Albert; Simonich, Cassandra; Goo, Leslie; Arendt, Heather; Kim, Helen J.; Lee, Jeong Hyun; Pugach, Pavel; Williams, Melissa; Debnath, Gargi; Moldt, Brian; van Breemen, Mariëlle J.; Isik, Gözde; Medina-Ramírez, Max; Back, Jaap Willem; Koff, Wayne; Julien, Jean-Philippe; Rakasz, Eva G.; Seaman, Michael S.; Guttman, Miklos; Lee, Kelly K.; Klasse, Per Johan; LaBranche, Celia; Schief, William R.; Wilson, Ian A.; Overbaugh, Julie; Burton, Dennis R.; Ward, Andrew B.; Montefiori, David C.; Dean, Hansi; Moore, John P.

    2015-01-01

    A challenge for HIV-1 immunogen design is inducing neutralizing antibodies (NAbs) against neutralization-resistant (Tier-2) viruses that dominate human transmissions. We show that a soluble recombinant HIV-1 envelope glycoprotein trimer that adopts a native conformation (BG505 SOSIP.664) induced NAbs potently against the sequence-matched Tier-2 virus in rabbits and similar but weaker responses in macaques. The trimer also consistently induced cross-reactive NAbs against more sensitive (Tier-1) viruses. Tier-2 NAbs recognized conformational epitopes that differed between animals and in some cases overlapped with those recognized by broadly neutralizing antibodies (bNAbs), whereas Tier-1 responses targeted linear V3 epitopes. A second trimer, B41 SOSIP.664, also induced a strong autologous Tier-2 NAb response in rabbits. Thus, native-like trimers represent a promising starting point for developing HIV-1 vaccines aimed at inducing bNAbs. PMID:26089353

  8. Cross-clade neutralizing antibodies against HIV-1 induced in rabbits by focusing the immune response on a neutralizing epitope

    SciTech Connect

    Zolla-Pazner, Susan; Cohen, Sandra; Pinter, Abraham; Krachmarov, Chavdar; Wrin, Terri; Wang Shixia; Lu Shan

    2009-09-15

    Studies were performed to induce cross-clade neutralizing antibodies (Abs) by testing various combinations of prime and boost constructs that focus the immune response on structurally-conserved epitopes in the V3 loop of HIV-1 gp120. Rabbits were immunized with gp120 DNA containing a V3 loop characterized by the GPGR motif at its tip, and/or with gp120 DNA with a V3 loop carrying the GPGQ motif. Priming was followed by boosts with V3-fusion proteins (V3-FPs) carrying the V3 sequence from a subtype B virus (GPGR motif), and/or with V3 sequences from subtypes A and C (GPGQ motif). The broadest and most consistent neutralizing responses were generated when using a clade C gp120 DNA prime and with the V3{sub B}-FP boost. Immune sera displayed neutralizing activity in three assays against pseudoviruses and primary isolates from subtypes A, AG, B, C, and D. Polyclonal Abs in the immune rabbit sera neutralized viruses that were not neutralized by pools of human anti-V3 monoclonal Abs. Greater than 80% of the neutralizing Abs were specific for V3, showing that the immune response could be focused on a neutralizing epitope and that vaccine-induced anti-V3 Abs have cross-clade neutralizing activity.

  9. Both Neutralizing and Non-Neutralizing Human H7N9 Influenza Vaccine-Induced Monoclonal Antibodies Confer Protection.

    PubMed

    Henry Dunand, Carole J; Leon, Paul E; Huang, Min; Choi, Angela; Chromikova, Veronika; Ho, Irvin Y; Tan, Gene S; Cruz, John; Hirsh, Ariana; Zheng, Nai-Ying; Mullarkey, Caitlin E; Ennis, Francis A; Terajima, Masanori; Treanor, John J; Topham, David J; Subbarao, Kanta; Palese, Peter; Krammer, Florian; Wilson, Patrick C

    2016-06-01

    Pathogenic H7N9 avian influenza viruses continue to represent a public health concern, and several candidate vaccines are currently being developed. It is vital to assess if protective antibodies are induced following vaccination and to characterize the diversity of epitopes targeted. Here we characterized the binding and functional properties of twelve H7-reactive human antibodies induced by a candidate A/Anhui/1/2013 (H7N9) vaccine. Both neutralizing and non-neutralizing antibodies protected mice in vivo during passive transfer challenge experiments. Mapping the H7 hemagglutinin antigenic sites by generating escape mutant variants against the neutralizing antibodies identified unique epitopes on the head and stalk domains. Further, the broadly cross-reactive non-neutralizing antibodies generated in this study were protective through Fc-mediated effector cell recruitment. These findings reveal important properties of vaccine-induced antibodies and provide a better understanding of the human monoclonal antibody response to influenza in the context of vaccines. PMID:27281570

  10. MHD Induced Neutral Beam Ion Loss from NSTX Plasmas

    SciTech Connect

    D.S. Darrow, E.D. Fredrickson, N.N. Gorelenkov, A.L. Roquemore, and K. Shinohara

    2007-12-13

    Bursts of ~60 kHz activity on Mirnov coils occur frequently in NSTX plasmas and these are accompanied by bursts of neutral beam ion loss over a range in pitch angles. These losses have been measured with a scintillator type loss probe imaged with a high speed (>10,000 frames/s) video camera, giving the evolution of the energy and pitch angle distributions of the lost neutral beam ions over the course of the events. The instability occurs below the TAE frequency in NSTX (~100 kHz) in high beta plasmas and may be a beta driven Alfvén acoustic (BAAE) mode.

  11. HIV-1 VACCINES. HIV-1 neutralizing antibodies induced by native-like envelope trimers.

    PubMed

    Sanders, Rogier W; van Gils, Marit J; Derking, Ronald; Sok, Devin; Ketas, Thomas J; Burger, Judith A; Ozorowski, Gabriel; Cupo, Albert; Simonich, Cassandra; Goo, Leslie; Arendt, Heather; Kim, Helen J; Lee, Jeong Hyun; Pugach, Pavel; Williams, Melissa; Debnath, Gargi; Moldt, Brian; van Breemen, Mariëlle J; Isik, Gözde; Medina-Ramírez, Max; Back, Jaap Willem; Koff, Wayne C; Julien, Jean-Philippe; Rakasz, Eva G; Seaman, Michael S; Guttman, Miklos; Lee, Kelly K; Klasse, Per Johan; LaBranche, Celia; Schief, William R; Wilson, Ian A; Overbaugh, Julie; Burton, Dennis R; Ward, Andrew B; Montefiori, David C; Dean, Hansi; Moore, John P

    2015-07-10

    A challenge for HIV-1 immunogen design is the difficulty of inducing neutralizing antibodies (NAbs) against neutralization-resistant (tier 2) viruses that dominate human transmissions. We show that a soluble recombinant HIV-1 envelope glycoprotein trimer that adopts a native conformation, BG505 SOSIP.664, induced NAbs potently against the sequence-matched tier 2 virus in rabbits and similar but weaker responses in macaques. The trimer also consistently induced cross-reactive NAbs against more sensitive (tier 1) viruses. Tier 2 NAbs recognized conformational epitopes that differed between animals and in some cases overlapped with those recognized by broadly neutralizing antibodies (bNAbs), whereas tier 1 responses targeted linear V3 epitopes. A second trimer, B41 SOSIP.664, also induced a strong autologous tier 2 NAb response in rabbits. Thus, native-like trimers represent a promising starting point for the development of HIV-1 vaccines aimed at inducing bNAbs.

  12. [Induce of laccase from Trametes gallica and its degradation on neutral dyes and organophosphorus pesticides].

    PubMed

    Jing, De-Jun; Huang, Jian-Bo; Yang, Zhou-Ping; Hu, Rong; Cheng, Zi-Zhang; Huang, Qian-Ming

    2011-12-01

    The characteristics of the induction of laccase in Trametes gallica under different initial cultural pH, incubation time by different inducers were discussed, as well as the effects of temperature, pH and time on laccase degradation of six dyes and four organophosphors. The results showed that RB-bright blue, ABTS and o-toluidine affected the production of laccase at different levels, and ABTS was the best inductive agent in our test conditions, whose optimal initial pH and incubation time were 4.0 and 13 days, respectively. The appropriate reaction temperature of the laccase produced was 38 degrees C, and it got a good stability, for it could retain 78.6% of the enzyme activity after 20 min holding at 40 degrees C. Mediated by ABTS, the optimal temperature for laccase to degrade the six types of neutral dyes could be divided into two cases, that was 30 degrees C (neutral black, neutral bordeaux, neutral pink, methyl orange) and 60 degrees C (neutral dark yellow, cresol red), the optimal pH were 6.0 (neutral black), 2.0 (neutral bordeaux, neutral pink) and 4.0 (methyl orange, neutral dark yellow, cresol red), respectively, while the optimal times separately were 6 h (methyl orange, neutral dark yellow, cresol red), 12 h (neutral pink) and 24 h (neutral bordeaux). And using the same inductive agent, the best temperature for laccase to degrade dimethoate, chlorpyrifos, trichlorfon and parathion-pyridazine was 25 degrees C, the suitable time was 9 h, and the optimal pH was 10.0 for dimethoate, chlorpyrifos and parathion-pyridazine, and 8.0 for trichlorfon. PMID:22384601

  13. Decoherence induced CPT violation and entangled neutral mesons

    SciTech Connect

    Bernabeu, J.; Mavromatos, Nick E.; Sarkar, Sarben

    2006-08-15

    We discuss two classes of semimicroscopic theoretical models of stochastic spacetime foam in quantum gravity and the associated effects on entangled states of neutral mesons, signalling an intrinsic breakdown of CPT invariance. One class of models deals with a specific model of foam, initially constructed in the context of noncritical (Liouville) string theory, but viewed here in the more general context of effective quantum-gravity models. The relevant Hamiltonian perturbation, describing the interaction of the meson with the foam medium, consists of off-diagonal stochastic metric fluctuations, connecting distinct mass eigenstates (or the appropriate generalization thereof in the case of K-mesons), and it is proportional to the relevant momentum transfer (along the direction of motion of the meson pair). There are two kinds of CPT-violating effects in this case, which can be experimentally disentangled: one (termed '{omega}-effect') is associated with the failure of the indistinguishability between the neutral meson and its antiparticle, and affects certain symmetry properties of the initial state of the two-meson system; the second effect is generated by the time evolution of the system in the medium of the spacetime foam, and can result in time-dependent contributions of the {omega}-effect type in the time profile of the two-meson state. Estimates of both effects are given, which show that, at least in certain models, such effects are not far from the sensitivity of experimental facilities available currently or in the near future. The other class of quantum-gravity models involves a medium of gravitational fluctuations which behaves like a 'thermal bath'. In this model both of the above-mentioned intrinsic CPT violation effects are not valid.

  14. Induction of pseudopregnancy in the American Black Bear (Ursus americanus).

    PubMed

    Schulz, Laura Clamon; Nelson, Ralph A; Pyter, Leah M; Bahr, Janice M

    2003-08-01

    The aim of this study was to determine whether American Black Bears (Ursus americanus) can experience a pseudopregnancy of the same duration as pregnancy. To do this, we treated three nonmated, captive female bears with human chorionic gonadotropin (hCG) during one breeding season, and saline during another. Progesterone concentrations were measured in monthly blood samples to determine whether pseudopregnancy had occurred. Elevated progesterone concentrations were observed in two out of three bears treated with hCG. We conclude that 1) Elevated progesterone concentrations can be induced in black bears by injection of 35 U/kg hCG during the mating season. 2) Bears can experience a pseudopregnancy, identical in length to pregnancy, in which progesterone profiles are indistinguishable from those of pregnancy.

  15. Induction of pseudopregnancy in the American Black Bear (Ursus americanus).

    PubMed

    Schulz, Laura Clamon; Nelson, Ralph A; Pyter, Leah M; Bahr, Janice M

    2003-08-01

    The aim of this study was to determine whether American Black Bears (Ursus americanus) can experience a pseudopregnancy of the same duration as pregnancy. To do this, we treated three nonmated, captive female bears with human chorionic gonadotropin (hCG) during one breeding season, and saline during another. Progesterone concentrations were measured in monthly blood samples to determine whether pseudopregnancy had occurred. Elevated progesterone concentrations were observed in two out of three bears treated with hCG. We conclude that 1) Elevated progesterone concentrations can be induced in black bears by injection of 35 U/kg hCG during the mating season. 2) Bears can experience a pseudopregnancy, identical in length to pregnancy, in which progesterone profiles are indistinguishable from those of pregnancy. PMID:12884278

  16. Large-Scale Examination of Factors Influencing Phosphopeptide Neutral Loss during Collision Induced Dissociation

    NASA Astrophysics Data System (ADS)

    Brown, Robert; Stuart, Scott S.; Houel, Stephane; Ahn, Natalie G.; Old, William M.

    2015-07-01

    Collision-induced dissociation (CID) remains the predominant mass spectrometry-based method for identifying phosphorylation sites in complex mixtures. Unfortunately, the gas-phase reactivity of phosphoester bonds results in MS/MS spectra dominated by phosphoric acid (H3PO4) neutral loss events, suppressing informative peptide backbone cleavages. To understand the major drivers of H3PO4 neutral loss, we performed robust nonparametric statistical analysis of local and distal sequence effects on the magnitude and variability of neutral loss, using a collection of over 35,000 unique phosphopeptide MS/MS spectra. In contrast to peptide amide dissociation pathways, which are strongly influenced by adjacent amino acid side chains, we find that neutral loss of H3PO4 is affected by both proximal and distal sites, most notably basic residues and the peptide N-terminal primary amine. Previous studies have suggested that protonated basic residues catalyze neutral loss through direct interactions with the phosphate. In contrast, we find that nearby basic groups decrease neutral loss regardless of mobility class, an effect only seen by stratifying spectra by charge-mobility. The most inhibitory bases are those immediately N-terminal to the phosphate, presumably because of steric hindrances in catalyzing neutral loss. Further evidence of steric effects is shown by the presence of proline, which can dramatically reduce the presence of neutral loss when between the phosphate and a possible charge donor. In mobile proton spectra, the N-terminus is the strongest predictor of high neutral loss, with proximity to the N-terminus essential for peptides to exhibit the highest levels of neutral loss.

  17. Large-Scale Examination of Factors Influencing Phosphopeptide Neutral Loss during Collision Induced Dissociation.

    PubMed

    Brown, Robert; Stuart, Scott A; Stuart, Scott S; Houel, Stephane; Ahn, Natalie G; Old, William M

    2015-07-01

    Collision-induced dissociation (CID) remains the predominant mass spectrometry-based method for identifying phosphorylation sites in complex mixtures. Unfortunately, the gas-phase reactivity of phosphoester bonds results in MS/MS spectra dominated by phosphoric acid (H3PO4) neutral loss events, suppressing informative peptide backbone cleavages. To understand the major drivers of H3PO4 neutral loss, we performed robust nonparametric statistical analysis of local and distal sequence effects on the magnitude and variability of neutral loss, using a collection of over 35,000 unique phosphopeptide MS/MS spectra. In contrast to peptide amide dissociation pathways, which are strongly influenced by adjacent amino acid side chains, we find that neutral loss of H3PO4 is affected by both proximal and distal sites, most notably basic residues and the peptide N-terminal primary amine. Previous studies have suggested that protonated basic residues catalyze neutral loss through direct interactions with the phosphate. In contrast, we find that nearby basic groups decrease neutral loss regardless of mobility class, an effect only seen by stratifying spectra by charge-mobility. The most inhibitory bases are those immediately N-terminal to the phosphate, presumably because of steric hindrances in catalyzing neutral loss. Further evidence of steric effects is shown by the presence of proline, which can dramatically reduce the presence of neutral loss when between the phosphate and a possible charge donor. In mobile proton spectra, the N-terminus is the strongest predictor of high neutral loss, with proximity to the N-terminus essential for peptides to exhibit the highest levels of neutral loss.

  18. Large-Scale Examination of Factors Influencing Phosphopeptide Neutral Loss during Collision Induced Dissociation

    PubMed Central

    Brown, Robert; Stuart, Scott A.; Houel, Stephane; Ahn, Natalie G.; Old, William M.

    2015-01-01

    Collision-induced dissociation (CID) remains the predominant mass spectrometry based method for identifying phosphorylation sites in complex mixtures. Unfortunately, the gas-phase reactivity of phosphoester bonds results in MS/MS spectra dominated by phosphoric acid (H3PO4) neutral loss events, suppressing informative peptide backbone cleavages. To understand the major drivers of H3PO4 neutral loss, we performed robust non-parametric statistical analysis of local and distal sequence effects on the magnitude and variability of neutral loss, using a collection of over 35,000 unique phosphopeptide MS/MS spectra. In contrast to peptide amide dissociation pathways, which are strongly influenced by adjacent amino acid side chains, we find that neutral loss of H3PO4 is affected by both proximal and distal sites, most notably basic residues and the peptide N-terminal primary amine. Previous studies have suggested that protonated basic residues catalyze neutral loss through direct interactions with the phosphate. In contrast, we find that nearby basic groups decrease neutral loss regardless of mobility class, an effect only seen by stratifying spectra by charge-mobility. The most inhibitory bases are those immediately N-terminal to the phosphate, presumably due to steric hindrances in catalyzing neutral loss. Further evidence of steric effects is shown by the presence of proline which can dramatically reduce the presence of neutral loss when between the phosphate and a possible charge donor. In mobile proton spectra the N-terminus is the strongest predictor of high neutral loss, with proximity to the N-terminus essential for peptides to exhibit the highest levels of neutral loss. PMID:25851653

  19. Two-Photon Absorption Laser Induced Fluorescence Measurements of Neutral Density in Helicon Plasma

    NASA Astrophysics Data System (ADS)

    Galante, Matthew

    2013-10-01

    Neutral particles play a critical role in nearly all plasmas, from the pedestal region of a tokamak fusion plasma to industrial plasma processing systems. In fusion plasmas, neutrals at the edge serve as both a source of particles and also a sink of momentum and energy. Control of the edge plasma density in tokamaks is critical for the transition to H-mode plasmas and the role of neutrals in modifying the plasma rotation in the edge is an area of active research. However, few methods exist to make localized, direct neutral density measurements. We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5 MW/cm2), narrow bandwidth (0.1 cm-1) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2 cm, a time resolution of 10 ns, and a measurement cadence of 20 Hz. In this talk I will describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and I will present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible with the TALIF system. Time and spatially resolved measurements also allow us to explore the effects of wall recycling and pulse repetition rates on the neutral density profile in the plasma source. Work supported in part by US DOE under DE-FC02-04ER54698.

  20. Neutral current induced {pi}{sup 0} production and neutrino magnetic moment

    SciTech Connect

    Athar, M. Sajjad; Chauhan, S.; Singh, S. K.

    2008-08-01

    We have studied the total cross section, Q{sup 2}, momentum and angular distributions for pions in the {nu}({nu}) induced {pi}{sup 0} production from nucleons. The calculations have been done for the weak production induced by the neutral current in the standard model and the electromagnetic production induced by neutrino magnetic moment. It has been found that with the present experimental limits on the muon neutrino magnetic moment {mu}{sub {nu}{sub {mu}}}, the electromagnetic contribution to the cross section for the {pi}{sup 0} production is small. The neutrino induced neutral current production of {pi}{sup 0}, while giving an alternative method to study the magnetic moment of neutrino {mu}{sub {nu}{sub {mu}}}, does not provide any improvement over the present experimental limit on {mu}{sub {nu}{sub {mu}}} from the observation of this process in future experiments at T2K and NO{nu}A.

  1. Laser-induced fluorescence of metal-atom impurities in a neutral beam

    SciTech Connect

    Burrell, C.F.; Pyle, R.V.; Sabetimani, Z.; Schlachter, A.S.

    1984-10-01

    The need to limit impurities in fusion devices to low levels is well known. We have investigated, by the technique of laser-induced fluorescence, the concentration of heavy-metal atoms in a neutral beam caused by their evaporation from the hot filaments in a conventional high-current multifilament hydrogen-ion source.

  2. Structural Constraints of Vaccine-Induced Tier-2 Autologous HIV Neutralizing Antibodies Targeting the Receptor-Binding Site.

    PubMed

    Bradley, Todd; Fera, Daniela; Bhiman, Jinal; Eslamizar, Leila; Lu, Xiaozhi; Anasti, Kara; Zhang, Ruijung; Sutherland, Laura L; Scearce, Richard M; Bowman, Cindy M; Stolarchuk, Christina; Lloyd, Krissey E; Parks, Robert; Eaton, Amanda; Foulger, Andrew; Nie, Xiaoyan; Karim, Salim S Abdool; Barnett, Susan; Kelsoe, Garnett; Kepler, Thomas B; Alam, S Munir; Montefiori, David C; Moody, M Anthony; Liao, Hua-Xin; Morris, Lynn; Santra, Sampa; Harrison, Stephen C; Haynes, Barton F

    2016-01-01

    Antibodies that neutralize autologous transmitted/founder (TF) HIV occur in most HIV-infected individuals and can evolve to neutralization breadth. Autologous neutralizing antibodies (nAbs) against neutralization-resistant (Tier-2) viruses are rarely induced by vaccination. Whereas broadly neutralizing antibody (bnAb)-HIV-Envelope structures have been defined, the structures of autologous nAbs have not. Here, we show that immunization with TF mutant Envs gp140 oligomers induced high-titer, V5-dependent plasma neutralization for a Tier-2 autologous TF evolved mutant virus. Structural analysis of autologous nAb DH427 revealed binding to V5, demonstrating the source of narrow nAb specificity and explaining the failure to acquire breadth. Thus, oligomeric TF Envs can elicit autologous nAbs to Tier-2 HIVs, but induction of bnAbs will require targeting of precursors of B cell lineages that can mature to heterologous neutralization.

  3. Two photon absorption laser induced fluorescence measurements of neutral density in a helicon plasmaa)

    NASA Astrophysics Data System (ADS)

    Galante, M. E.; Magee, R. M.; Scime, E. E.

    2014-05-01

    We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5 MW/cm2), narrow bandwidth (0.1 cm-1) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2 cm, a time resolution of 10 ns, and a measurement cadence of 20 Hz. Here, we describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the DIII-D tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished with a single lens through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and we present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible. Time resolved measurements also allow us to explore the evolution of the neutral hydrogen density and temperature and effects of wall recycling. We find that the atomic neutral density grows rapidly at the initiation of the discharge, reaching the steady-state value within 1 ms. Additionally, we find that neutral hydrogen atoms are born with 0.08 eV temperatures, not 2 eV as is typically assumed.

  4. Two photon absorption laser induced fluorescence measurements of neutral density in a helicon plasma

    SciTech Connect

    Galante, M. E.; Magee, R. M.; Scime, E. E.

    2014-05-15

    We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5 MW/cm{sup 2}), narrow bandwidth (0.1 cm{sup −1}) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2 cm, a time resolution of 10 ns, and a measurement cadence of 20 Hz. Here, we describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the DIII-D tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished with a single lens through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and we present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible. Time resolved measurements also allow us to explore the evolution of the neutral hydrogen density and temperature and effects of wall recycling. We find that the atomic neutral density grows rapidly at the initiation of the discharge, reaching the steady-state value within 1 ms. Additionally, we find that neutral hydrogen atoms are born with 0.08 eV temperatures, not 2 eV as is typically assumed.

  5. Effects of Cellulolytic Ruminal Bacteria and of Cell Extracts on Germination of Euonymus americanus L. Seeds.

    PubMed

    Howard, Gary T; Elliott, Larry P

    1988-01-01

    In past attempts, the experimental germination of the seeds of Euonymus americanus L. in vitro has had little success. However, treatment of seeds with ruminal fluid containing viable microflora has been successful in stimulating germination. In the presence of the cellulolytic ruminal bacterium, Clostridium cellobioparum ATCC 15832, seeds of E. americanus were stimulated to germinate. Subsequent studies were designed to determine whether the bacterium synthesized a cellulolytic enzyme responsible for initiating germination. The cell-free endocellulase from C. cellobioparum induced germination of the seeds. To support the hypothesis that the endocellulase from C. cellobioparum was responsible for triggering germination, a 1,4-beta-d-glucan glucanohydrolase (EC 3.2.1.4) from Penicillum funiculosum was used to treat the seeds. In addition, no germination was obtained from seeds treated with a commercial exocellulase enzyme. Also, Ruminococcus flavefaciens FD-1 was found to initiate germination of E. americanus seeds. Thus, cellulase activity is indicated in the degradation of the testa of the seed, allowing imbibition and germination.

  6. Neutral Current {nu} Induced Reactions in Nuclei at Supernova Neutrino Energies

    SciTech Connect

    Chauhan, S.; Athar, M. Sajjad; Singh, S. K.

    2011-11-23

    We calculate cross sections for the neutral current induced neutrino/antineutrino reaction from {sup 208}Pb target and applied it to study Supernova neutrino event rates. The calculations are done in local density approximation taking into account Pauli blocking, Fermi motion effects and renormalization of weak transition strengths in the nuclear medium. The numerical results for the neutrino nucleus total cross sections have been averaged over the various Supernova neutrino/antineutrino fluxes available in literature.

  7. Spontaneously regressing oral papillomas induce systemic antibodies that neutralize canine oral papillomavirus.

    PubMed

    Ghim, S; Newsome, J; Bell, J; Sundberg, J P; Schlegel, R; Jenson, A B

    2000-06-01

    Canine oral papillomavirus (COPV) infection of naive beagle dogs causes oral papillomas, most of which spontaneously regress. Regressor beagles do not develop new oral papillomas because of COPV type-specific, cell-mediated immunity, COPV neutralizing antibodies, or both. Formalin-fixed native and recombinant COPV vaccines that target the systemic immune system induce neutralizing antibodies that prevent development of oral papillomas. This study was designed to determine whether spontaneously regressing mucosal papillomas also targeted the systemic immune system to induce circulating, neutralizing IgG antibodies that protect against infection by COPV. To accomplish this goal, IgG was fractionated from sera collected from weanling beagles and regressor beagles and tested for conferring protection by passive immunization. Serum was tested by ELISA for antibodies against intact virions and then pooled for passive transfer to naive beagles. Preimmune sera were neither reactive by ELISA nor protective by passive transfer. On the other hand, IgG antibodies from regressor beagles were reactive by ELISA and passive transfer conferred protection against COPV challenge. Circulating IgG antibodies induced by spontaneous regression of canine oral papillomas protect beagles against intraoral infection by COPV, a model for mucosotropic HPV. PMID:10816383

  8. Human monoclonal antibodies against West Nile virus induced by natural infection neutralize at a postattachment step.

    PubMed

    Vogt, Matthew R; Moesker, Bastiaan; Goudsmit, Jaap; Jongeneelen, Mandy; Austin, S Kyle; Oliphant, Theodore; Nelson, Steevenson; Pierson, Theodore C; Wilschut, Jan; Throsby, Mark; Diamond, Michael S

    2009-07-01

    West Nile virus (WNV) is a neurotropic flavivirus that is now a primary cause of epidemic encephalitis in North America. Studies of mice have demonstrated that the humoral immune response against WNV limits primary infection and protects against a secondary challenge. The most-potent neutralizing mouse monoclonal antibodies (MAbs) recognize an epitope on the lateral ridge of domain III (DIII-lr) of the envelope (E) protein. However, studies with serum from human patients show that antibodies against the DIII-lr epitope comprise, at best, a minor component of the human anti-WNV antibody response. Herein, we characterize in detail two WNV-specific human MAbs, CR4348 and CR4354, that were isolated from B-cell populations of convalescent patients. These MAbs strongly neutralize WNV infection of cultured cells, protect mice against lethal infection in vivo, and yet poorly recognize recombinant forms of the E protein. Instead, CR4348 and CR4354 bind determinants on intact WNV virions and subviral particles in a pH-sensitive manner, and neutralization is altered by mutations at the dimer interface in domain II and the hinge between domains I and II, respectively. CR4348 and CR4354 human MAbs neutralize infection at a postattachment step in the viral life cycle, likely by inhibiting acid-induced fusion within the endosome.

  9. Model of photo-induced neutral-ionic phase transition in organic charge-transfer salts

    NASA Astrophysics Data System (ADS)

    Yartsev, V. M.

    1998-01-01

    One-dimensional donor-acceptor mixed chains are modeled by a periodic DADA tetramer. Electron coupling to intramolecular vibrations are taken into account explicitly. Generalized adiabatic potentials are calculated for the cases of regular and dimerized stacks which are characteristic, respectively, of quasi-neutral (N) and quasi-ionic (I) phases of a tetrathiafulvalene-chloranil compound. A sharp difference in life-times of photo-induced I-states in the N-phase and N-states in the I-phase is discussed within the periodic DADA tetramer model.

  10. Low energy electron induced reactions in fluorinated acetamide - probing negative ions and neutral stable counterparts*

    NASA Astrophysics Data System (ADS)

    Kopyra, Janina; König-Lehmann, Constanze; Illenberger, Eugen; Warneke, Jonas; Swiderek, Petra

    2016-06-01

    Electron impact to trifluoroacetamide (CF3CONH2, TFAA) in the energy range 0-12 eV leads to a variety of negative fragment ions which are formed via dissociative electron attachment (DEA). The underlying reactions range from single bond cleavages to remarkably complex reactions that lead to loss of the neutral units HF, H2O and HNCO as deduced from their directly observed ionic counterparts (M - H2O)-, (M - HF)- and (M - HNCO)-. Also formed are the pseudo-halogen ions CN- and OCN-. All these reactions proceed dominantly via a resonance located near 1 eV, i.e., electrons at subexcitation energies trigger reactions involving multiple bond cleavages. The electron induced generation of the neutral molecules HF, H2O and HNCO in condensed TFAA films is probed by temperature controlled thermal desorption spectrometry (TDS) which can be viewed as a complementary techniques to gas-phase experiments in DEA to directly probe the neutral counterparts. Contribution to the Topical Issue "Advances in Positron and Electron Scattering", edited by Paulo Limao-Vieira, Gustavo Garcia, E. Krishnakumar, James Sullivan, Hajime Tanuma and Zoran Petrovic.

  11. Immune Focusing and Enhanced Neutralization Induced by HIV-1 gp140 Chemical Cross-Linking

    PubMed Central

    Schiffner, T.; Kong, L.; Duncan, C. J. A.; Back, J. W.; Benschop, J. J.; Shen, X.; Huang, P. S.; Stewart-Jones, G. B.; DeStefano, J.; Seaman, M. S.; Tomaras, G. D.; Montefiori, D. C.; Schief, W. R.

    2013-01-01

    Experimental vaccine antigens based upon the HIV-1 envelope glycoproteins (Env) have failed to induce neutralizing antibodies (NAbs) against the majority of circulating viral strains as a result of antibody evasion mechanisms, including amino acid variability and conformational instability. A potential vaccine design strategy is to stabilize Env, thereby focusing antibody responses on constitutively exposed, conserved surfaces, such as the CD4 binding site (CD4bs). Here, we show that a largely trimeric form of soluble Env can be stably cross-linked with glutaraldehyde (GLA) without global modification of antigenicity. Cross-linking largely conserved binding of all potent broadly neutralizing antibodies (bNAbs) tested, including CD4bs-specific VRC01 and HJ16, but reduced binding of several non- or weakly neutralizing antibodies and soluble CD4 (sCD4). Adjuvanted administration of cross-linked or unmodified gp140 to rabbits generated indistinguishable total gp140-specific serum IgG binding titers. However, sera from animals receiving cross-linked gp140 showed significantly increased CD4bs-specific antibody binding compared to animals receiving unmodified gp140. Moreover, peptide mapping of sera from animals receiving cross-linked gp140 revealed increased binding to gp120 C1 and V1V2 regions. Finally, neutralization titers were significantly elevated in sera from animals receiving cross-linked gp140 rather than unmodified gp140. We conclude that cross-linking favors antigen stability, imparts antigenic modifications that selectively refocus antibody specificity and improves induction of NAbs, and might be a useful strategy for future vaccine design. PMID:23843636

  12. Description-based reappraisal regulate the emotion induced by erotic and neutral images in a Chinese population

    PubMed Central

    Peng, Jiaxin; Qu, Chen; Gu, Ruolei; Luo, Yue-Jia

    2013-01-01

    Previous emotion-regulation research has shown that the late positive potential (LPP) is sensitive to the down-regulation of emotion; however, whether LPP is also sensitive to the up-regulation of emotion remains unclear. The present study examined the description-based reappraisal effects on the up-regulation of positive emotions induced by erotic and neutral images in a Chinese population. Self-reported ratings and event-related potential (ERP) were recorded when subjects viewed pleasant and neutral images, which were shown after either a neutral or positive description. Self-reported results showed that images following positive descriptions were rated as more pleasant compared to images following neutral descriptions. ERP results revealed that the P2, P3, and slow wave (SW) components were larger for erotic pictures than for neutral pictures, while the positive description condition yielded attenuated erotic image-induced P2, P3 and SW and increased SW induced by neutral images. The results demonstrated that description-based reappraisal, as a method of reappraisal, significantly modulates the emotional experience and ERP responses to erotic and neutral images. PMID:23335894

  13. Apoptosis induced by islet amyloid polypeptide soluble oligomers is neutralized by diabetes-associated specific antibodies

    PubMed Central

    Bram, Yaron; Frydman-Marom, Anat; Yanai, Inbal; Gilead, Sharon; Shaltiel-Karyo, Ronit; Amdursky, Nadav; Gazit, Ehud

    2014-01-01

    Soluble oligomeric assemblies of amyloidal proteins appear to act as major pathological agents in several degenerative disorders. Isolation and characterization of these oligomers is a pivotal step towards determination of their pathological relevance. Here we describe the isolation of Type 2 diabetes-associated islet amyloid polypeptide soluble cytotoxic oligomers; these oligomers induced apoptosis in cultured pancreatic cells, permeated model lipid vesicles and interacted with cell membranes following complete internalization. Moreover, antibodies which specifically recognized these assemblies, but not monomers or amyloid fibrils, were exclusively identified in diabetic patients and were shown to neutralize the apoptotic effect induced by these oligomers. Our findings support the notion that human IAPP peptide can form highly toxic oligomers. The presence of antibodies identified in the serum of diabetic patients confirms the pathological relevance of the oligomers. In addition, the newly identified structural epitopes may also provide new mechanistic insights and a molecular target for future therapy. PMID:24589570

  14. Visual optics in toads (Bufo americanus).

    PubMed

    Mathis, U; Schaeffel, F; Howland, H C

    1988-06-01

    Aspects of visual optics were investigated in the American toad (Bufo americanus). The development of the refractive state of the eye during metamorphosis was followed with IR photoretinoscopy. Frozen sections documented the changes in optical parameters before and after metamorphosis. There is a difference in light sensitivity between juvenile and adult toads. Binocular accommodation in adult toads was observed. 1. IR photoretinoscopic measurements showed that the refractive state of the eye changed very rapidly during metamorphosis, about 10 D/h while the animal entered the terrestrial habitat. 2. Frozen sections showed that the almost spherical lens in a tadpole eye had flattened in a just metamorphosed toad's eye while at the same time the distance of the lens to the retina had decreased. However, the morphological measurements were not sufficiently sensitive to record the relatively small changes in ocular dimensions that were responsible for the rapid changes in refractive state during metamorphosis. 3. Schematic eyes, with homogeneous and non homogeneous lenses, were constructed for tadpoles, juvenile toads, and adult toads. 4. Nonparaxial raytracing studies in schematic eyes suggested that the lenses of animals of the three developmental stages tadpole, juvenile toad, and adult are not homogeneous but have a refractive index gradient. The raytracing studies indicated that the refractive index gradient is different for the different developmental stages, being highest in the tadpole lens. 5. The observations of toads during feeding behavior at different light levels showed an increased light sensitivity in the adult nocturnal toads in contrast to the juvenile animals, which are diurnal. The increased light sensitivity could partly be explained with an increase in aperture and an increase in red rod outer segments. To fully explain the higher light sensitivity in adult toads, changes in neuronal parameters had to be assumed. 6. Retinoscopic measurements of

  15. Sarcocystis oreamni n. sp. from the mountain goat (oreamnos americanus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Numerous species of Sarcocystis have been reported from wild ruminants but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of 3 of 7 mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; 1 had ...

  16. Disorder-induced heating of ultracold neutral plasmas created from atoms in partially filled optical lattices

    NASA Astrophysics Data System (ADS)

    Murphy, D.; Sparkes, B. M.

    2016-08-01

    We quantify the disorder-induced heating (DIH) of ultracold neutral plasmas (UCNPs) created from cold atoms in optical lattices with partial filling fractions, using a conservation of energy model involving the spatial correlations of the initial state and the equation of state in thermal equilibrium for a one-component plasma. We show, for experimentally achievable filling fractions, that the ionic Coulomb coupling parameter could be increased to a degree comparable to other proposed DIH-mitigation schemes. Molecular dynamics simulations were performed with compensation for finite-size and periodic boundary effects, which agree with calculations using the model. Reduction of DIH using optical lattices will allow for the study of strongly coupled plasma physics using low-density, low-temperature, laboratory-based plasmas, and lead to improved brightness in UCNP-based cold electron and ion beams, where DIH is otherwise a fundamental limitation to beam focal sizes and diffraction imaging capability.

  17. Disorder-induced heating of ultracold neutral plasmas created from atoms in partially filled optical lattices.

    PubMed

    Murphy, D; Sparkes, B M

    2016-08-01

    We quantify the disorder-induced heating (DIH) of ultracold neutral plasmas (UCNPs) created from cold atoms in optical lattices with partial filling fractions, using a conservation of energy model involving the spatial correlations of the initial state and the equation of state in thermal equilibrium for a one-component plasma. We show, for experimentally achievable filling fractions, that the ionic Coulomb coupling parameter could be increased to a degree comparable to other proposed DIH-mitigation schemes. Molecular dynamics simulations were performed with compensation for finite-size and periodic boundary effects, which agree with calculations using the model. Reduction of DIH using optical lattices will allow for the study of strongly coupled plasma physics using low-density, low-temperature, laboratory-based plasmas, and lead to improved brightness in UCNP-based cold electron and ion beams, where DIH is otherwise a fundamental limitation to beam focal sizes and diffraction imaging capability. PMID:27627236

  18. [Neutralization of the hemorrhagic effect induced by Bothrops asper (Serpentes: Viperidae) venom with tropical plant extracts].

    PubMed

    Castro, O; Gutiérrez, J M; Barrios, M; Castro, I; Romero, M; Umaña, E

    1999-09-01

    Organic extracts representing 48 species included in 30 families of Costa Rican tropical plants were evaluated for their ability to neutralize hemorrhagic activity induced by the venom of the snake Bothrops asper. A bioassay in mice was used, based on intradermal injection of either venom or venom-extract mixtures followed by the measurement of hemorrhagic areas. Total inhibition of hemorrhage was observed with the ethanolic, ethyl acetate and aqueous extracts of Bursera simaruba, Clusia torresii, C. palmana, Croton draco, Persea americana, Phoebe brenesii, Pimenta dioica, Sapindus saponaria, Smilax cuculmeca and Virola koschnyi. Chemical analysis of these extracts identified catequines, flavones, anthocyanines and condensated tannins, which may be responsible for the inhibitory effect observed, probably owing to the chelation of the zinc required for the catalytic activity of venom's hemorrhagic metalloproteinases.

  19. Neutrino-Induced Neutral-Current Reaction Cross Sections for r-PROCESS Nuclei

    NASA Astrophysics Data System (ADS)

    Langanke, K.; Kolbe, E.

    2002-11-01

    Neutrino-induced reactions play an important role during and after the r-process, if the latter occurs in an environment with extreme neutrino fluxes such as the neutrino-driven wind model or neutron star mergers. Recently we have evaluated the charged-current neutrino-nucleus cross sections relevant for r-process simulations. We extend our approach here to the neutral-current cross sections. Our tabulation considers neutron-rich nuclei with neutron numbers N=41-135 and charge numbers Z=21-82 and lists total as well as partial neutron spallation cross sections. The calculations have been performed within the random phase approximation considering multipole transitions with J<=3 and both parities. The supernova neutrino spectrum is described by a Fermi-Dirac distribution with various temperature parameters between T=2.8 MeV and T=10 MeV and with the degeneracy parameters α=0 and α=3.

  20. Mild pressure induces rapid accumulation of neutral lipid (triacylglycerol) in Chlorella spp.

    PubMed

    Praveenkumar, Ramasamy; Kim, Bohwa; Lee, Jiye; Vijayan, Durairaj; Lee, Kyubock; Nam, Bora; Jeon, Sang Goo; Kim, Dong-Myung; Oh, You-Kwan

    2016-11-01

    Effective enhancement of neutral lipid (especially triacylglycerol, TAG) content in microalgae is an important issue for commercialization of microalgal biorefineries. Pressure is a key physical factor affecting the morphological, physiological, and biochemical behaviors of organisms. In this paper, we report a new stress-based method for induction of TAG accumulation in microalgae (specifically, Chlorella sp. KR-1 and Ch. sp. AG20150) by very-short-duration application of mild pressure. Pressure treatments of 10-15bar for 2h resulted in a considerable, ∼55% improvement of the 10-100g/Lcells' TAG contents compared with the untreated control. The post-pressure-treatment increase of cytoplasmic TAG granules was further confirmed by transmission electron microscopy (TEM). Notwithstanding the increased TAG content, the total lipid content was not changed by pressurization, implying that pressure stress possibly induces rapid remodeling/transformation of algal lipids rather than de novo biosynthesis of TAG. PMID:27634024

  1. Alkaline, acid, and neutral phosphatase activities are induced during development in Myxococcus xanthus.

    PubMed Central

    Weinberg, R A; Zusman, D R

    1990-01-01

    One of the signals that has been reported to be important in stimulating fruiting body formation of Myxococcus xanthus is starvation for phosphate. We therefore chose to study phosphatase activity during M. xanthus development. Many phosphatases can cleave the substrate p-nitrophenol phosphate. Using this substrate in buffers at various pHs, we obtained a profile of phosphatase activities during development and germination of M. xanthus. These experiments indicated that there are five patterns of phosphatase activity in M. xanthus: two vegetative and three developmental. The two uniquely vegetative activities have pH optima at 7.2 and 8.5. Both require magnesium and both are inhibited by the reducing agent dithiothreitol. The developmental (spores) patterns of activity have pH optima of 5.2, 7.2, and 8.5. All three activities are Mg independent. Only the alkaline phosphatase activity is inhibited by dithiothreitol. The acid phosphatase activity is induced very early in development, within the first 2 to 4 h. Both the neutral and alkaline phosphatase Mg-independent activities are induced much later, about the time that myxospores become evident (24 to 30 h). The three activities are greatly diminished upon germination; however, the kinetics of loss differ for all three. The acid phosphatase activity declines very rapidly, the neutral activity begins to decline only after spores begin to convert to rods, and the alkaline phosphatase activity remains high until the time the cells begin to divide. All three developmental activities were measured in the developmental signalling mutants carrying asg, csg, and dsg. The pattern of expression obtained in the mutants was consistent with that of other developmentally regulated genes which exhibit similar patterns of expression during development. The ease with which phosphatases can be assayed should make the activities described in this report useful biochemical markers of stages of both fruiting body formation and

  2. Neutralization of Osteopontin Ameliorates Acute Lung Injury Induced by Intestinal Ischemia-Reperfusion.

    PubMed

    Hirano, Yohei; Aziz, Monowar; Yang, Weng-Lang; Ochani, Mahendar; Wang, Ping

    2016-10-01

    Intestinal ischemia-reperfusion (I/R) is associated with acute respiratory distress syndrome. Osteopontin (OPN), a glycoprotein secreted from immune-reactive cells, plays a deleterious role in various inflammatory diseases. Considering OPN as a pro-inflammatory molecule, we hypothesize that the treatment with its neutralizing antibody (anti-OPN Ab) protects mice against intestinal I/R-induced acute lung injury (ALI). Intestinal I/R was induced in mice by superior mesenteric artery occlusion with a vascular clip. After 45 min of occlusion, the clip was removed and anti-OPN Ab (25 μg/mouse) or normal IgG isotype control (25 μg/mouse) was immediately administrated intravenously. Blood, small intestine, and lung tissues were collected at 4 h after reperfusion for various analyses. After intestinal I/R, mRNA and protein levels of OPN were significantly induced in the small intestine, lungs, and blood relative to sham-operated animals. Compared with the IgG control group, treatment of anti-OPN Ab significantly reduced plasma levels of pro-inflammatory cytokine and chemokine (IL-6 and MIP-2) and organ injury markers (AST, ALT, and LDH). The histological architecture of the gut and lung tissues in anti-OPN Ab-treated intestinal I/R-induced mice showed significant improvement versus the IgG control mice. The lung inflammation measured by the levels of IL-6, IL-1β, and MIP-2 was also significantly downregulated in the anti-OPN Ab-treated mice as compared with the IgG control mice. Besides, the lung MPO and neutrophil infiltration in anti-OPN Ab-treated mice showed significant reduction as compared with the IgG control animals. In conclusion, we have demonstrated beneficial outcomes of anti-OPN Ab treatment in protecting against ALI, implicating a novel therapeutic potential in intestinal I/R. PMID:26974422

  3. Neutralization of Osteopontin Ameliorates Acute Lung Injury Induced by Intestinal Ischemia-Reperfusion.

    PubMed

    Hirano, Yohei; Aziz, Monowar; Yang, Weng-Lang; Ochani, Mahendar; Wang, Ping

    2016-10-01

    Intestinal ischemia-reperfusion (I/R) is associated with acute respiratory distress syndrome. Osteopontin (OPN), a glycoprotein secreted from immune-reactive cells, plays a deleterious role in various inflammatory diseases. Considering OPN as a pro-inflammatory molecule, we hypothesize that the treatment with its neutralizing antibody (anti-OPN Ab) protects mice against intestinal I/R-induced acute lung injury (ALI). Intestinal I/R was induced in mice by superior mesenteric artery occlusion with a vascular clip. After 45 min of occlusion, the clip was removed and anti-OPN Ab (25 μg/mouse) or normal IgG isotype control (25 μg/mouse) was immediately administrated intravenously. Blood, small intestine, and lung tissues were collected at 4 h after reperfusion for various analyses. After intestinal I/R, mRNA and protein levels of OPN were significantly induced in the small intestine, lungs, and blood relative to sham-operated animals. Compared with the IgG control group, treatment of anti-OPN Ab significantly reduced plasma levels of pro-inflammatory cytokine and chemokine (IL-6 and MIP-2) and organ injury markers (AST, ALT, and LDH). The histological architecture of the gut and lung tissues in anti-OPN Ab-treated intestinal I/R-induced mice showed significant improvement versus the IgG control mice. The lung inflammation measured by the levels of IL-6, IL-1β, and MIP-2 was also significantly downregulated in the anti-OPN Ab-treated mice as compared with the IgG control mice. Besides, the lung MPO and neutrophil infiltration in anti-OPN Ab-treated mice showed significant reduction as compared with the IgG control animals. In conclusion, we have demonstrated beneficial outcomes of anti-OPN Ab treatment in protecting against ALI, implicating a novel therapeutic potential in intestinal I/R.

  4. Neutralization of IL-10 exacerbates cycloheximide-induced hepatocellular apoptosis and necrosis.

    PubMed

    Kumagai, Kazuyoshi; Ito, Kazumi; Ando, Yosuke; Hakamata, Shinobu; Teranishi, Munehiro; Nakayama, Hiroyuki; Manabe, Sunao

    2009-06-01

    Cycloheximide (CHX)-induced liver injury in rats has been characterized by hepatocellular apoptosis and necrosis. We previously reported that Kupffer cell inactivation causes a reduction of IL-10 production, resulting in the exacerbation of CHX-induced liver injury. In this study, we directly evaluate the role of IL-10 in liver injury by a pretreatment with anti-IL-10 neutralizing antibody (IL-10Ab). Rats were given goat IgG or IL-10Ab before being treated with CHX (CHX group or IL-10Ab/CHX group). In the CHX group, the CHX treatment markedly induced hepatic mRNA and serum protein levels of IL-10. The up-regulation of IL-10 was significantly suppressed in the IL-10Ab/CHX group. Blocking IL-10 in the IL-10Ab/CHX group led to greater increases in hepatic mRNA and serum levels of proinflammatory cytokines, such as TNF-alpha and IL-6. The IL-10Ab/CHX group developed more severe hepatocellular apoptosis, neutrophil transmigration, and necrotic change of hepatocytes compared with the CHX group. The caspase activities and mRNA levels of Cc120, LOX-1, and E-selectin in the livers were significantly higher in the IL-10Ab/CHX group than the CHX group. These results demonstrate that IL-10 plays an important role in counteracting the effect of proinflammatory cytokines, such as a TNF signaling cascade, and in attenuating the CHX-induced liver injury. PMID:19395591

  5. Obatoclax kills anaplastic thyroid cancer cells by inducing lysosome neutralization and necrosis

    PubMed Central

    Champa, Devora; Orlacchio, Arturo; Patel, Bindi; Ranieri, Michela; Shemetov, Anton A; Verkhusha, Vladislav V; Cuervo, Ana Maria; Di Cristofano, Antonio

    2016-01-01

    Poorly differentiated and anaplastic thyroid carcinomas are very aggressive, almost invariably lethal neoplasms for which no effective treatment exists. These tumors are intrinsically resistant to cell death, even when their driver oncogenic signaling pathways are inhibited. We have undertaken a detailed analysis, in mouse and human thyroid cancer cells, of the mechanism through which Obatoclax, a pan-inhibitor of the anti-apoptotic proteins of the BCL2 family, effectively reduces tumor growth in vitro and in vivo. We demonstrate that Obatoclax does not induce apoptosis, but rather necrosis of thyroid cancer cells, and that non-transformed thyroid cells are significantly less affected by this compound. Surprisingly, we show that Obatoclax rapidly localizes to the lysosomes and induces loss of acidification, block of lysosomal fusion with autophagic vacuoles, and subsequent lysosomal permeabilization. Notably, prior lysosome neutralization using different V-ATPase inhibitors partially protects cancer cells from the toxic effects of Obatoclax. Although inhibition of autophagy does not affect Obatoclax-induced cell death, selective down-regulation of ATG7, but not of ATG5, partially impairs Obatoclax effects, suggesting the existence of autophagy-independent functions for ATG7. Strikingly, Obatoclax killing activity depends only on its accumulation in the lysosomes, and not on its interaction with BCL2 family members. Finally, we show that also other lysosome-targeting compounds, Mefloquine and LLOMe, readily induce necrosis in thyroid cancer cells, and that Mefloquine significantly impairs tumor growth in vivo, highlighting a clear vulnerability of these aggressive, apoptosis-resistant tumors that can be therapeutically exploited. PMID:27144341

  6. Comparative tissue expression of American lobster (Homarus americanus) immune genes during bacterial and scuticociliate challenge.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Wang, Haili; Greenwood, Spencer J

    2015-12-01

    The American lobster (Homarus americanus) fishery is the most economically significant fishery in Canada; although comparatively little is known about the lobsters' response to pathogenic challenge. This is the first study to investigate the expression of immune genes in tissues outside of the lobster hepatopancreas in response to challenges by the Gram-positive bacteria, Aerococcus viridans var. homari or the scuticociliate parasite, Anophryoides haemophila. The hepatopancreas has been regarded as the major humoral immune organ in crustaceans, but the contribution of other organs and tissues to the molecular immune response has largely been overlooked. This study used RT-qPCR to monitor the gene expression of several immune genes including three anti-lipopolysaccharide isoforms (ALF) Homame ALF-B1, Homame ALF-C1 and ALFHa-1, acute phase serum amyloid protein A (SAA), as well as thioredoxin and hexokinase, in antennal gland and gill tissues. Our findings indicate that the gene expression of the SAA and all ALF isoforms in the antennal gland and gill tissues increased in response to pathogenic challenge. However, there was differential expression of individual ALF isoforms that were dependent on both the tissue, and the pathogen used in the challenge. The gene expression changes of several immune genes were found to be higher in the antennal gland than have been previously reported for the hepatopancreas. This study demonstrates that increased immune gene expression from the gill and antennal gland over the course of pathogen induced disease contributes to the immune response of H. americanus.

  7. Comparative tissue expression of American lobster (Homarus americanus) immune genes during bacterial and scuticociliate challenge.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Wang, Haili; Greenwood, Spencer J

    2015-12-01

    The American lobster (Homarus americanus) fishery is the most economically significant fishery in Canada; although comparatively little is known about the lobsters' response to pathogenic challenge. This is the first study to investigate the expression of immune genes in tissues outside of the lobster hepatopancreas in response to challenges by the Gram-positive bacteria, Aerococcus viridans var. homari or the scuticociliate parasite, Anophryoides haemophila. The hepatopancreas has been regarded as the major humoral immune organ in crustaceans, but the contribution of other organs and tissues to the molecular immune response has largely been overlooked. This study used RT-qPCR to monitor the gene expression of several immune genes including three anti-lipopolysaccharide isoforms (ALF) Homame ALF-B1, Homame ALF-C1 and ALFHa-1, acute phase serum amyloid protein A (SAA), as well as thioredoxin and hexokinase, in antennal gland and gill tissues. Our findings indicate that the gene expression of the SAA and all ALF isoforms in the antennal gland and gill tissues increased in response to pathogenic challenge. However, there was differential expression of individual ALF isoforms that were dependent on both the tissue, and the pathogen used in the challenge. The gene expression changes of several immune genes were found to be higher in the antennal gland than have been previously reported for the hepatopancreas. This study demonstrates that increased immune gene expression from the gill and antennal gland over the course of pathogen induced disease contributes to the immune response of H. americanus. PMID:26551049

  8. Precipitation of energetic neutral atoms and induced non-thermal escape fluxes from the Martian atmosphere

    SciTech Connect

    Lewkow, N. R.; Kharchenko, V.

    2014-08-01

    The precipitation of energetic neutral atoms, produced through charge exchange collisions between solar wind ions and thermal atmospheric gases, is investigated for the Martian atmosphere. Connections between parameters of precipitating fast ions and resulting escape fluxes, altitude-dependent energy distributions of fast atoms and their coefficients of reflection from the Mars atmosphere, are established using accurate cross sections in Monte Carlo (MC) simulations. Distributions of secondary hot (SH) atoms and molecules, induced by precipitating particles, have been obtained and applied for computations of the non-thermal escape fluxes. A new collisional database on accurate energy-angular-dependent cross sections, required for description of the energy-momentum transfer in collisions of precipitating particles and production of non-thermal atmospheric atoms and molecules, is reported with analytic fitting equations. Three-dimensional MC simulations with accurate energy-angular-dependent cross sections have been carried out to track large ensembles of energetic atoms in a time-dependent manner as they propagate into the Martian atmosphere and transfer their energy to the ambient atoms and molecules. Results of the MC simulations on the energy-deposition altitude profiles, reflection coefficients, and time-dependent atmospheric heating, obtained for the isotropic hard sphere and anisotropic quantum cross sections, are compared. Atmospheric heating rates, thermalization depths, altitude profiles of production rates, energy distributions of SH atoms and molecules, and induced escape fluxes have been determined.

  9. Neutral Sphingomyelinase in Physiological and Measles Virus Induced T Cell Suppression

    PubMed Central

    Collenburg, Lena; Grassmé, Heike; Schneider-Schaulies, Sibylle

    2014-01-01

    T cell paralysis is a main feature of measles virus (MV) induced immunosuppression. MV contact mediated activation of sphingomyelinases was found to contribute to MV interference with T cell actin reorganization. The role of these enzymes in MV-induced inhibition of T cell activation remained equally undefined as their general role in regulating immune synapse (IS) activity which relies on spatiotemporal membrane patterning. Our study for the first time reveals that transient activation of the neutral sphingomyelinase 2 (NSM2) occurs in physiological co-stimulation of primary T cells where ceramide accumulation is confined to the lamellum (where also NSM2 can be detected) and excluded from IS areas of high actin turnover. Genetic ablation of the enzyme is associated with T cell hyper-responsiveness as revealed by actin dynamics, tyrosine phosphorylation, Ca2+-mobilization and expansion indicating that NSM2 acts to suppress overshooting T cell responses. In line with its suppressive activity, exaggerated, prolonged NSM2 activation as occurring in co-stimulated T cells following MV exposure was associated with aberrant compartmentalization of ceramides, loss of spreading responses, interference with accumulation of tyrosine phosphorylated protein species and expansion. Altogether, this study for the first time reveals a role of NSM2 in physiological T cell stimulation which is dampening and can be abused by a virus, which promotes enhanced and prolonged NSM2 activation to cause pathological T cell suppression. PMID:25521388

  10. Precisely Molded Nanoparticle Displaying DENV-E Proteins Induces Robust Serotype-Specific Neutralizing Antibody Responses

    PubMed Central

    Hoekstra, Gabriel; Yi, Xianwen; Stone, Michelle; Horvath, Katie; Miley, Michael J.; DeSimone, Joseph; Luft, Chris J.; de Silva, Aravinda M.

    2016-01-01

    Dengue virus (DENV) is the causative agent of dengue fever and dengue hemorrhagic fever. The virus is endemic in over 120 countries, causing over 350 million infections per year. Dengue vaccine development is challenging because of the need to induce simultaneous protection against four antigenically distinct DENV serotypes and evidence that, under some conditions, vaccination can enhance disease due to specific immunity to the virus. While several live-attenuated tetravalent dengue virus vaccines display partial efficacy, it has been challenging to induce balanced protective immunity to all 4 serotypes. Instead of using whole-virus formulations, we are exploring the potentials for a particulate subunit vaccine, based on DENV E-protein displayed on nanoparticles that have been precisely molded using Particle Replication in Non-wetting Template (PRINT) technology. Here we describe immunization studies with a DENV2-nanoparticle vaccine candidate. The ectodomain of DENV2-E protein was expressed as a secreted recombinant protein (sRecE), purified and adsorbed to poly (lactic-co-glycolic acid) (PLGA) nanoparticles of different sizes and shape. We show that PRINT nanoparticle adsorbed sRecE without any adjuvant induces higher IgG titers and a more potent DENV2-specific neutralizing antibody response compared to the soluble sRecE protein alone. Antigen trafficking indicate that PRINT nanoparticle display of sRecE prolongs the bio-availability of the antigen in the draining lymph nodes by creating an antigen depot. Our results demonstrate that PRINT nanoparticles are a promising platform for delivering subunit vaccines against flaviviruses such as dengue and Zika. PMID:27764114

  11. Myostatin Neutralization Results in Preservation of Muscle Mass and Strength in Preclinical Models of Tumor-Induced Muscle Wasting.

    PubMed

    Smith, Rosamund C; Cramer, Martin S; Mitchell, Pamela J; Capen, Andrew; Huber, Lysiane; Wang, Rong; Myers, Laura; Jones, Bryan E; Eastwood, Brian J; Ballard, Darryl; Hanson, Jeff; Credille, Kelly M; Wroblewski, Victor J; Lin, Boris K; Heuer, Josef G

    2015-07-01

    Skeletal muscle wasting occurs in a great majority of cancer patients with advanced disease and is associated with a poor prognosis and decreased survival. Myostatin functions as a negative regulator of skeletal muscle mass and has recently become a therapeutic target for reducing the loss of skeletal muscle and strength associated with clinical myopathies. We generated neutralizing antibodies to myostatin to test their potential use as therapeutic agents to attenuate the skeletal muscle wasting due to cancer. We show that our neutralizing antimyostatin antibodies significantly increase body weight, skeletal muscle mass, and strength in non-tumor-bearing mice with a concomitant increase in mean myofiber area. The administration of these neutralizing antibodies in two preclinical models of cancer-induced muscle wasting (C26 colon adenocarcinoma and PC3 prostate carcinoma) resulted in a significant attenuation of the loss of muscle mass and strength with no effect on tumor growth. We also show that the skeletal muscle mass- and strength-preserving effect of the antibodies is not affected by the coadministration of gemcitabine, a common chemotherapeutic agent, in both non-tumor-bearing mice and mice bearing C26 tumors. In addition, we show that myostatin neutralization with these antibodies results in the preservation of skeletal muscle mass following reduced caloric intake, a common comorbidity associated with advanced cancer. Our findings support the use of neutralizing antimyostatin antibodies as potential therapeutics for cancer-induced muscle wasting.

  12. Fisheries-induced neutral and adaptive evolution in exploited fish populations and consequences for their adaptive potential

    PubMed Central

    Marty, Lise; Dieckmann, Ulf; Ernande, Bruno

    2015-01-01

    Fishing may induce neutral and adaptive evolution affecting life-history traits, and molecular evidence has shown that neutral genetic diversity has declined in some exploited populations. Here, we theoretically study the interplay between neutral and adaptive evolution caused by fishing. An individual-based eco-genetic model is devised that includes neutral and functional loci in a realistic ecological setting. In line with theoretical expectations, we find that fishing induces evolution towards slow growth, early maturation at small size and higher reproductive investment. We show, first, that the choice of genetic model (based on either quantitative genetics or gametic inheritance) influences the evolutionary recovery of traits after fishing ceases. Second, we analyse the influence of three factors possibly involved in the lack of evolutionary recovery: the strength of selection, the effect of genetic drift and the loss of adaptive potential. We find that evolutionary recovery is hampered by an association of weak selection differentials with reduced additive genetic variances. Third, the contribution of fisheries-induced selection to the erosion of functional genetic diversity clearly dominates that of genetic drift only for the traits related to maturation. Together, our results highlight the importance of taking into account population genetic variability in predictions of eco-evolutionary dynamics. PMID:25667602

  13. Weak charged and neutral current induced one pion production off the nucleon

    NASA Astrophysics Data System (ADS)

    Rafi Alam, M.; Sajjad Athar, M.; Chauhan, S.; Singh, S. K.

    2016-02-01

    We present a study of neutrino/antineutrino induced charged current (CC) and neutral current (NC) single pion production (SPP) off the nucleon. For this, we have considered P33(1232) resonance, nonresonant background (NRB) terms, other higher resonances like P11(1440), S11(1535), D13(1520), S11(1650) and P13(1720). For the NRB terms a microscopic approach based on SU(2) nonlinear sigma model has been used. The vector form factors for the resonances are obtained by using the relationship between the electromagnetic resonance form factors and helicity amplitudes provided by MAID. Axial coupling C5A(0) in the case of P33(1232) resonance is obtained by fitting the ANL and BNL ν-deuteron reanalyzed scattering data. The results are presented with and without deuteron effect for the total scattering cross-sections for all possible channels, viz. νl(ν¯l)+N → l-(l+)+N‧+πi and νl(ν¯l)+N → νl(ν¯l)+N‧ + πi, where N,N‧ = p,n, πi = π± or π0 and l = e,μ.

  14. A Measurement of Neutrino-Induced Charged-Current Neutral Pion Production

    SciTech Connect

    Nelson, Robert H.

    2010-01-01

    This work presents the first comprehensive measurement of neutrino-induced charged-current neutral pion production (CCπ0) off a nuclear target. The Mini Booster Neutrino Experiment (MiniBooNE) and Booster Neutrino Beam (BNB) are discussed in detail. MiniBooNE is a high-statistics (~ 1, 000, 000 interactions) low-energy (Evϵ 2 0.5 - 2.0 GeV) neutrino experiment located at Fermilab. The method for selecting and reconstructing CCπ0 events is presented. The π0 and μ- are fully reconstructed in the final state allowing for the measurement of, among other things, the neutrino energy. The total observable CCπ0 cross-section is presented as a function of neutrino energy, along with five differential cross-sections in terms of the final state kinematics and Q2. The results are combined to yield a flux-averaged total cross-section of <σ>Φ = (9.2 ± 0.3stat. ± 1.5syst.) × 10-39 cm2/CH2 at energy 965 MeV. These measurements will aid future neutrino experiments with the prediction of their neutrino interaction rates.

  15. Effect on extrapulmonary sepsis-induced acute lung injury by hemoperfusion with neutral microporous resin column.

    PubMed

    Huang, Zhao; Wang, Si-rong; Yang, Zi-li; Liu, Ji-yun

    2013-08-01

    The aim of this study was to investigate the effect of neutral microporous resin hemoperfusion on oxygenation improvement, removal of inflammatory cytokines in plasma and bronchoalveolar lavage, and mortality in acute lung injury induced by extrapulmonary sepsis. Forty-six patients with acute lung injury induced by extrapulmonary sepsis were randomized to HA type hemoperfusion treatment (N=25) or standard therapy (N=21). Those undergoing hemoperfusion treatment received HA330 hemoperfusion. We measured the plasma and bronchoalveolar lavage concentrations of TNF-α and IL-1, and the following parameters were compared between the control group and the hemoperfusion group on days 0, 3 and 7: lung injury measurements (arterial oxygen tension/fractional inspired oxygen ratio, lung injury score, chest X-ray score); interstitial edema of lung (extravascular lung water). Duration of mechanical ventilation, hospital, 28-day, and intensive care unit mortality were also observed. Patients treated with HA hemoperfusion showed a significant removal of plasma and bronchoalveolar lavage TNF-α and IL-1 over time while in the study. Patients in the HA group also demonstrated not only significant improvement of PaO2 /FiO2 , but also decreased Lung Injury Score and chest X-ray score at days 3 and 7. Furthermore, the measurements of the arterial oxygen tension/fractional inspired oxygen ratio, lung injury score and extravascular lung water (EVLWI) significantly correlated with and the concentration of cytokines in the plasma (all P<0.05). The HA hemoperfusion treatment group had a significant reduction in duration of mechanical ventilation, length of intensive care unit stay, and intensive care unit mortality. Significant removal of inflammatory cytokines from circulation and lung by hemoperfusion treatment using the HA type cartridge may contribute to the improvement of lung injury and intensive care unit outcome in extrapulmonary septic patients. PMID:23931889

  16. TGF-β Neutralization Enhances AngII-Induced Aortic Rupture and Aneurysm in Both Thoracic and Abdominal Regions

    PubMed Central

    Howatt, Deborah A.; Balakrishnan, Anju; Moorleghen, Jessica J.; Cassis, Lisa A.; Daugherty, Alan

    2016-01-01

    AngII and TGF-β interact in development of thoracic and abdominal aortic diseases, although there are many facets of this interaction that have not been clearly defined. The aim of the present study was to determine the effects of TGF-β neutralization on AngII induced-aortic pathologies. Male C57BL/6J mice were administered with either a rabbit or mouse TGF-β neutralizing antibody and then infused with AngII. The rabbit TGF-β antibody modestly reduced serum TGF-β concentrations, with no significant enhancements to AngII-induced aneurysm or rupture. Administration of this rabbit TGF-β antibody in mice led to high serum titers against rabbit IgG that may have attenuated the neutralization. In contrast, a mouse TGF-β antibody (1D11) significantly increased rupture in both the ascending and suprarenal aortic regions, but only at doses that markedly decreased serum TGF-β concentrations. High doses of 1D11 antibody significantly increased AngII-induced ascending and suprarenal aortic dilatation. To determine whether TGF-β neutralization had effects in mice previously infused with AngII, the 1D11 antibody was injected into mice that had been infused with AngII for 28 days and were observed during continued infusion for a further 28 days. Despite near ablations of serum TGF-β concentrations, the mouse TGF-β antibody had no effect on aortic rupture or dimensions in either ascending or suprarenal region. These data provide further evidence that AngII-induced aortic rupture is enhanced greatly by TGF-β neutralization when initiated before pathogenesis. PMID:27104863

  17. TGF-β Neutralization Enhances AngII-Induced Aortic Rupture and Aneurysm in Both Thoracic and Abdominal Regions.

    PubMed

    Chen, Xiaofeng; Rateri, Debra L; Howatt, Deborah A; Balakrishnan, Anju; Moorleghen, Jessica J; Cassis, Lisa A; Daugherty, Alan

    2016-01-01

    AngII and TGF-β interact in development of thoracic and abdominal aortic diseases, although there are many facets of this interaction that have not been clearly defined. The aim of the present study was to determine the effects of TGF-β neutralization on AngII induced-aortic pathologies. Male C57BL/6J mice were administered with either a rabbit or mouse TGF-β neutralizing antibody and then infused with AngII. The rabbit TGF-β antibody modestly reduced serum TGF-β concentrations, with no significant enhancements to AngII-induced aneurysm or rupture. Administration of this rabbit TGF-β antibody in mice led to high serum titers against rabbit IgG that may have attenuated the neutralization. In contrast, a mouse TGF-β antibody (1D11) significantly increased rupture in both the ascending and suprarenal aortic regions, but only at doses that markedly decreased serum TGF-β concentrations. High doses of 1D11 antibody significantly increased AngII-induced ascending and suprarenal aortic dilatation. To determine whether TGF-β neutralization had effects in mice previously infused with AngII, the 1D11 antibody was injected into mice that had been infused with AngII for 28 days and were observed during continued infusion for a further 28 days. Despite near ablations of serum TGF-β concentrations, the mouse TGF-β antibody had no effect on aortic rupture or dimensions in either ascending or suprarenal region. These data provide further evidence that AngII-induced aortic rupture is enhanced greatly by TGF-β neutralization when initiated before pathogenesis.

  18. Laser Induced Fluorescence Spectroscopy of Neutral and Ionized Polycyclic Aromatic Hydrocarbons in a Cosmic Simulation Chamber

    NASA Astrophysics Data System (ADS)

    Bejaoui, Salma; Salama, Farid

    2015-08-01

    Polycyclic aromatic hydrocarbon (PAH) molecules are considered the best carriers to account for the ubiquitous infrared emission bands. PAHs have also been proposed as candidates to explain the diffuse interstellar bands (DIBs), a series of absorption features seen on the interstellar extinction curve and are plausible carriers for the extended red emission (ERE), a photoluminescent process associated with a wide variety of interstellar environments. Extensive efforts have been devoted over the past two decades to characterize the physical and chemical properties of PAH molecules and ions in space. Absorption spectra of PAH molecules and ions trapped in solid matrices have been compared to the DIBs [1, 2]. Absorption spectra of several cold, isolated gas-phase PAHs have also been measured under experimental conditions that mimic the interstellar conditions [see 3 for a review]. The purpose of this study is to provide a new dimension to the existing spectroscopic database of neutral and single ionized PAHs that is largely based on absorption spectra by adding emission spectroscopy data. The measurements are based on the laser-induced fluorescence (LIF) technique [4] and are performed with the Pulsed Discharge Nozzle (PDN) of the COSmIC laboratory facility at NASA Ames laboratory. The PDN generates plasma in a free supersonic jet expansion to simulate the physical and the chemical conditions in interstellar environments. We focus, here, on the fluorescence spectra of large neutral PAHs and their cations where there is a lack of fluorescence spectroscopy data. The astronomical implications of the data (e.g., ERE) are examinedReferences[1] F. Salama, E. Bakes, L.J. Allamandola, A.G.G.M. Tielens, Astrophys. J., 458 (1996) p.621[2] F. Salama, The ISO Revolution, EDP Sciences, Les Ulis, France (1999) p.65[3] Salama F., In Organic Matter in Space, IAU Symposium 251, Kwok & Sandford Eds.Cambridge University Press,4, S251,(2008), p. 357 (2008) and references therein.[4

  19. Neutralizing and cross-neutralizing antibody titres induced by bivalent and quadrivalent human papillomavirus vaccines in the target population of organized vaccination programmes.

    PubMed

    Barzon, Luisa; Squarzon, Laura; Masiero, Serena; Pacenti, Monia; Marcati, Giorgia; Mantelli, Barbara; Gabrielli, Liliana; Pascucci, Maria Grazia; Lazzarotto, Tiziana; Caputo, Antonella; Palù, Giorgio

    2014-09-15

    Aim of this investigator-initiated study was to evaluate and compare the titres of neutralizing and cross-neutralizing antibodies (NAbs) induced by the bivalent (Cervarix(®)) and quadrivalent (Gardasil(®)) HPV vaccines in a cohort of girls aged 11-13 years from organized vaccination programmes. To this aim, HPV16 and HPV18 NAbs were measured by pseudovirion-based neutralization assays in serum collected at 1-6 months after the third vaccine dose in 107 girls vaccinated with Cervarix(®) and 126 vaccinated with Gardasil(®), while HPV31 and HPV45 cross-NAbs were tested in the first 50 consecutive girls of both vaccine groups. The results of this study demonstrated that all vaccinated girls developed HPV16 and HPV18 NAbs, with the exception of two Gardasil(®) vaccinees with undetectable HPV18 NAbs. Geometric mean titres (GMTs) of both HPV16 and HPV18 NAbs were significantly higher in Cervarix(®) than in Gardasil(®) vaccinees [HPV16 NAb GMT 22,136 (95% CI, 18,811-26,073) vs 5092 (4230-6151), respectively; P<0.0001; HPV18 NAb GMT 11,962 (9536-14,363) vs 1804 (1574-2110), respectively; P<0.0001]. Cross-NAbs to HPV31 and HPV45 were detected more frequently Cervarix(®) (HPV31 NAb positivity rates 92.7% and 36%, respectively; P<0.05) than in Gardasil(®) vaccinees (HPV45 NAb positivity rates 56% and 6%, respectively; P<0.0001). The titres of cross-NAbs against HPV31 and HPV45 were also significantly higher in Cervarix(®) than in Gardasil(®) vaccinees [HPV31 NAb GMT 157.2 (95% CI, 92-269) vs 13.0 (6.5-25.8), respectively; P<0.0001; HPV45 NAb GMT 4.7 (2.1-10.2) vs 1.3 (0.3-3.1), respectively; P<0.01]. In conclusion, in adolescent girls vaccinated within organized vaccination programmes, HPV vaccines drive the generation not only of NAbs to HPV vaccine types, but also of cross-NAbs. The bivalent vaccine induced significantly higher HPV16 and HPV18 NAb titres and more frequently and at higher titre HPV31 and HPV45 cross-NAbs than the quadrivalent vaccine.

  20. Carnosine and neocuproine as neutralizing agents for copper overload-induced damages in cultured human cells.

    PubMed

    Arnal, Nathalie; de Alaniz, María J T; Marra, Carlos A

    2011-07-15

    Copper is dangerous when it is present in excess, mainly because it can participate in the Fenton reaction, which produces radical species. As a consequence of copper pollution, people are involuntarily exposed to a copper overload under sub-clinical and sub-symptomatological conditions, which may be very difficult to detect. Thus, we investigated (i) the possible use of the chelator molecules carnosine and neocuproine to prevent the Cu overload-induced damage on cellular lipids and proteins, as tested in human cell culture systems, and (ii) the differential response of these two chelating agents in relation to their protective action, and the type of copper ion involved in the process, by using two types of human cultured cells (HepG2 and A-549). Cu treatment clearly enhanced (p<0.01) the formation of protein carbonyls, thiobarbituric acid-reactive substances (TBARS) and the concentration of nitrate plus nitrites, with a concomitant decrease in cell survival, as estimated by the trypan dye exclusion test and lactate dehydrogenase leakage. Simultaneous treatment with Cu and carnosine or neocuproine indicated that carnosine is more efficient than neocuproine in protecting both types of cells from the effect of cupric ions on both the cell-associated damages and the decrease in the cellular viability. This observation was supported by the fact that carnosine is not only a complexing agent for Cu(II), but also an effective antioxidant that can dismutate superoxide radicals, scavenge hydroxyl radicals and neutralize TBARS formation. Carnosine should be investigated in more detail in order to establish its putative utility as an agent to prevent copper-associated damages in biological systems.

  1. An oral Aujeszky's disease vaccine (YS-400) induces neutralizing antibody in pigs

    PubMed Central

    2016-01-01

    Purpose Aujeszky's disease (AD) is an economically important disease affecting both wild and domestic pigs of the species Sus scrofa. A previous study yielded serological evidence of AD in Korean wild boars, which could spread AD to other animals. A new Aujeszky's disease virus (ADV) bait vaccine is required to prevent AD outbreaks in swine. In the present study, we investigated the safety and immunogenicity of a gE-deleted marker vaccine, strain YS-400, in young domestic pigs. Materials and Methods The YS-400 strain was propagated in Vero cells, and the trial ADV bait vaccine (a vaccine blister in a matrix including an attractant) was prepared. Pigs were orally immunized with the vaccine (2 mL, 107.5 TCID50/mL) delivered using a syringe or in the bait vaccine. The animals were observed for 9 weeks after vaccination, and immunogenicity was assessed using a virus neutralization (VN) test and enzyme linked immunosorbent assay. Results The YS-400 strain was non-pathogenic to pigs when given orally and induced high VN titers (1:32-1:128) 6 weeks post-administration. Of the pigs given the ADV bait vaccine twice or three times, 40% were seropositive by 2 weeks, and 100% were seropositive by 7 weeks after the first dose. Pigs that consumed the AD bait vaccine three times developed VN titers that were slightly higher than those of pigs given the vaccine twice. Conclusion Domestic pigs given the trial ADV bait vaccine exhibited no adverse effects and developed high VN titers against ADV, indicating that the YS-400 strain is safe and can prevent ADV infection in domestic pigs. PMID:27489803

  2. Pressure-Induced Conductivity in a Neutral Nonplanar Spin-Localized Radical.

    PubMed

    Souto, Manuel; Cui, HengBo; Peña-Álvarez, Miriam; Baonza, Valentín G; Jeschke, Harald O; Tomic, Milan; Valentí, Roser; Blasi, Davide; Ratera, Imma; Rovira, Concepció; Veciana, Jaume

    2016-09-14

    There is a growing interest in the development of single-component molecular conductors based on neutral organic radicals that are mainly formed by delocalized planar radicals, such as phenalenyl or thiazolyl radicals. However, there are no examples of systems based on nonplanar and spin-localized C-centered radicals exhibiting electrical conductivity due to their large Coulomb energy (U) repulsion and narrow electronic bandwidth (W) that give rise to a Mott insulator behavior. Here we present a new type of nonplanar neutral radical conductor attained by linking a tetrathiafulvalene (TTF) donor unit to a neutral polychlorotriphenylmethyl radical (PTM) with the important feature that the TTF unit enhances the overlap between the radical molecules as a consequence of short intermolecular S···S interactions. This system becomes semiconducting upon the application of high pressure thanks to increased electronic bandwidth and charge reorganization opening the way to develop a new family of neutral radical conductors. PMID:27281384

  3. Measurement of muon neutrino and antineutrino induced single neutral pion production cross sections

    SciTech Connect

    Anderson, Colin E.

    2011-05-01

    Elucidating the nature of neutrino oscillation continues to be a goal in the vanguard of the efforts of physics experiment. As neutrino oscillation searches seek an increasingly elusive signal, a thorough understanding of the possible backgrounds becomes ever more important. Measurements of neutrino-nucleus interaction cross sections are key to this understanding. Searches for νμ → νe oscillation - a channel that may yield insight into the vanishingly small mixing parameter θ13, CP violation, and the neutrino mass hierarchy - are particularly susceptible to contamination from neutral current single π0 (NC 1π0) production. Unfortunately, the available data concerning NC 1π0 production are limited in scope and statistics. Without satisfactory constraints, theoretical models of NC 1π0 production yield substantially differing predictions in the critical Eν ~ 1 GeV regime. Additional investigation of this interaction can ameliorate the current deficiencies. The Mini Booster Neutrino Experiment (MiniBooNE) is a short-baseline neutrino oscillation search operating at the Fermi National Accelerator Laboratory (Fermilab). While the oscillation search is the principal charge of the MiniBooNE collaboration, the extensive data (~ 106 neutrino events) offer a rich resource with which to conduct neutrino cross section measurements. This work concerns the measurement of both neutrino and antineutrino NC 1π0 production cross sections at MiniBooNE. The size of the event samples used in the analysis exceeds that of all other similar experiments combined by an order of magnitude. We present the first measurements of the absolute NC 1π0 cross section as well as the first differential cross sections in both neutrino and antineutrino mode. Specifically, we measure single differential cross sections with respect to pion momentum and pion angle. We find the

  4. Tiratricol neutralizes bacterial endotoxins and reduces lipopolysaccharide-induced TNF-alpha production in the cell.

    PubMed

    Cascales, Laura; Mas-Moruno, Carlos; Tamborero, Silvia; Aceña, José Luis; Sanz-Cervera, Juan F; Fustero, Santos; Cruz, Luis J; Mora, Puig; Albericio, Fernando; Pérez-Payá, Enrique

    2008-10-01

    The screening of a commercially available library of compounds has proved a successful strategy for the identification of a lead compound in a drug discovery programme. Here, we analysed 880 off-patent drugs, which initially comprised the Prestwick Chemical library, as sources of bacterial endotoxin neutralizers. We identified 3,3',5-triiodo-thyroacetic acid (tiratricol) as a non-antibacterial compound that neutralizes the toxic lipopolysaccharide. PMID:18844678

  5. Cretinism in a North American black bear (Ursus americanus).

    PubMed

    Duncan, Robert B; Jones, Jeryl C; Moll, H David; Moon, Martha M; Blodgett, Dennis J; Vaughan, Michael R

    2002-01-01

    Congenital hyperplastic goiter and cretinism were documented in a 16 month-old male North American black bear (Ursus americanus). The cub was captured at approximately 8 months of age and maintained for an additional 8 months in captivity. Clinical signs included growth retardation, clumsiness, and facial dysmorphism. Hypothyroidism was documented by determining serum triiodothyronine (T3) and thyroxine (T4) levels. Lysosomal storage disease was ruled out by measuring various lysosomal enzyme activities. Serologic, radiographic, computed tomographic, necropsy, and histopathologic findings were consistent with congenital hypothyroidism and cretinism. PMID:11866041

  6. Neutralization of interleukin-17A delays progression of silica-induced lung inflammation and fibrosis in C57BL/6 mice

    SciTech Connect

    Chen, Ying; Li, Cuiying; Weng, Dong; Song, Laiyu; Tang, Wen; Dai, Wujing; Yu, Ye; Liu, Fangwei; Zhao, Ming; Lu, Chunwei; Chen, Jie

    2014-02-15

    Silica exposure can cause lung inflammation and fibrosis, known as silicosis. Interleukin-17A (IL-17A) and Th17 cells play a pivotal role in controlling inflammatory diseases. However, the roles of IL-17A and Th17 cells in the progress of silica-induced inflammation and fibrosis are poorly understood. This study explored the effects of IL-17A on silica-induced inflammation and fibrosis. We used an anti-mouse IL-17A antibody to establish an IL-17A-neutralized mice model, and mice were exposed to silica to establish an experimental silicosis model. We showed that IL-17A neutralization delayed neutrophil accumulation and progression of silica-induced lung inflammation and fibrosis. IL-17A neutralization reduced the percentage of Th17 in CD4 + T cells, decreased IL-6 and IL-1β expression, and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A delayed silica-induced Th1/Th2 immune and autoimmune responses. These results suggest that IL-17A neutralization alleviates early stage silica-induced lung inflammation and delays progression of silica-induced lung inflammation and fibrosis. Neutralization of IL-17A suppressed Th17 cell development by decreasing IL-6 and/or IL-1β and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A also delayed the Th1/Th2 immune response during silica-induced lung inflammation and fibrosis. IL-17A may play a pivotal role in the early phase of silica-induced inflammation and may mediate the Th immune response to influence silica-induced lung inflammation and fibrosis in mice. - Highlights: • Neutralization of IL-17A alleviated silica-induced lung inflammation of early stage. • Neutralization of IL-17A decreased Th17 cells and increased Tregs. • IL-17A mediated the reciprocal relationship of Th17/Tregs by IL-6 and/or IL-1β. • Neutralization of IL-17A delayed silica-induced Th1/Th2 immune response. • Neutralization of IL-17A delayed silica-induced lung

  7. Desorption induced by electronic transitions (DIET) of neutral fragments from chemisorbed biological molecular systems

    NASA Astrophysics Data System (ADS)

    Abdoul-Carime, H.; Dugal, P. C.; Sanche, L.

    2000-04-01

    Low-energy electron stimulated desorption of neutral fragments from oligomers chemisorbed onto a gold surface is investigated within the 1-30 eV range. The oligonucleotides are anchored to the surface via a sulfur-bound technique similar to the procedure used in molecular self-assemblies. We show that under electron impact the dissociation of DNA bases occurs, leading to the production of CN, OCN and/or H 2NCN neutral species, which are the most intense observable yields. The incident electron energy dependence of these desorbed neutral species exhibits typical signatures of dissociative electron attachment initiated by the formation of shape and core-excited resonances below 20 eV, whereas usually non-resonant processes (i.e. dipolar dissociation or dissociative ionization) become predominant above 20 eV.

  8. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties

    PubMed Central

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

    Various strategies involving the use of hepatitis C virus (HCV) E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system. PMID:26966906

  9. Hepatitis C Virus E1 and E2 Proteins Used as Separate Immunogens Induce Neutralizing Antibodies with Additive Properties.

    PubMed

    Beaumont, Elodie; Roch, Emmanuelle; Chopin, Lucie; Roingeard, Philippe

    2016-01-01

    Various strategies involving the use of hepatitis C virus (HCV) E1 and E2 envelope glycoproteins as immunogens have been developed for prophylactic vaccination against HCV. However, the ideal mode of processing and presenting these immunogens for effective vaccination has yet to be determined. We used our recently described vaccine candidate based on full-length HCV E1 or E2 glycoproteins fused to the heterologous hepatitis B virus S envelope protein to compare the use of the E1 and E2 proteins as separate immunogens with their use as the E1E2 heterodimer, in terms of immunogenetic potential and the capacity to induce neutralizing antibodies. The specific anti-E1 and anti-E2 antibody responses induced in animals immunized with vaccine particles harboring the heterodimer were profoundly impaired with respect to those in animals immunized with particles harboring E1 and E2 separately. Moreover, the anti-E1 and anti-E2 antibodies had additive neutralizing properties that increase the cross-neutralization of heterologous strains of various HCV genotypes, highlighting the importance of including both E1 and E2 in the vaccine for an effective vaccination strategy. Our study has important implications for the optimization of HCV vaccination strategies based on HCV envelope proteins, regardless of the platform used to present these proteins to the immune system.

  10. HIV-1 gp41 Core with Exposed Membrane-Proximal External Region Inducing Broad HIV-1 Neutralizing Antibodies

    PubMed Central

    Zhou, Leilei; Xu, Liling; Jiang, Shibo; Chen, Ying-hua

    2011-01-01

    The membrane-proximal external region (MPER) of the HIV-1 gp41 consists of epitopes for the broadly cross-neutralizing monoclonal antibodies 2F5 and 4E10. However, antigens containing the linear sequence of these epitopes are unable to elicit potent and broad neutralizing antibody responses in vaccinated hosts, possibly because of inappropriate conformation of these epitopes. Here we designed a recombinant antigen, designated NCM, which comprises the N- and C-terminal heptad repeats that can form a six-helix bundle (6HB) core and the MPER domain of gp41. Two mutations (T569A and I675V) previously reported to expose the neutralization epitopes were introduced into NCM to generate mutants named NCM(TA), NCM(IV), and NCM(TAIV). Our results showed that NCM and its mutants could react with antibodies specific for 6HB and MPER of gp41, suggesting that these antigens are in the form of a trimer of heterodimer (i.e., 6HB) with three exposed MPER tails. Antigen with double mutations, NCM(TAIV), elicited much stronger antibody response in rabbits than immunogens with single mutation, NCM(TA) and NCM(IV), or no mutation, NCM. The purified MPER-specific antibodies induced by NCM(TAIV) exhibited broad neutralizing activity, while the purified 6HB-specific antibodies showed no detectable neutralizing activity. Our recombinant antigen design supported by an investigation of its underlying molecular mechanisms provides a strong scientific platform for the discovery of a gp41 MPER-based AIDS vaccine. PMID:21483871

  11. Hookworm (Necator americanus) larval enzymes disrupt human vascular endothelium.

    PubMed

    Souadkia, Nahed; Brown, Alan; Leach, Lopa; Pritchard, David I

    2010-09-01

    Knowledge of the molecular mechanisms used by Necator americanus larvae to penetrate the human skin and the vasculature would aid the development of effective vaccines against this important pathogen. In this work, the impact of N. americanus exsheathing fluid (EF) and excretory/secretory products (ES) on the endothelial barrier was examined using human umbilical vein endothelial cells (HUVEC). Cellular responses were assessed by investigating molecular changes at cell-cell junctions and by determining levels of secreted IL-6, IL-8, and vascular endothelial growth factor (VEGF) in the culture medium. It would appear that a repertoire of larval proteases caused a dose-related increase in endothelial permeability as characterized by a decrease in monolayer resistance with increased permeation of tracer-albumin. These barrier changes were associated with disruption of junctional vascular endothelial cadherin (VE-cadherin) and F-actin and an increase in endothelial secretion of IL-6 and IL-8. Our data suggest that larval proteases play an important role in negotiating the endothelium.

  12. Cysteamine-induced inhibition of acid neutralization and the increase in hydrogen ion back-diffusion in duodenal mucosa

    SciTech Connect

    Ohe, K.; Okada, Y.; Fujiwara, T.; Inoue, M.; Miyoshi, A.

    1982-03-01

    To investigate the possible impairment of defensive mechanisms in cysteamine-induced duodenal ulceration, the effect of cysteamine on the neutralization of acid by the duodenum and the back-diffusion of hydrogen ions into the duodenal mucosa has been studied. The results obtained were as follows. (1) The intraduodenal pH started to decrease between 3 and 4 hr after cysteamine injection. (2) By perfusion of the duodenal loop excluding the opening of bile and pancreatic ducts, the amount of hydrogen ions (H+) neutralized was found to be significantly lower in cysteamine-treated animals than in the controls. (3) the back-diffusion of luminal H+ into the duodenal mucosa, estimated by measuring the H+ disappearance from the test solution including 100 mM HCl, was significantly increased by cysteamine. From these findings, it has been concluded that cysteamine reduces the resistance of duodenal mucosa to acid coming from the stomach.

  13. Gas-phase reactions of charged phenyl radicals with neutral biomolecules evaporated by laser-induced acoustic desorption.

    PubMed

    Petzold, Christopher J; Ramírez-Arizmendi, Luis E; Heidbrink, Jenny L; Pérez, James; Kenttämaa, Hilkka I

    2002-02-01

    A generally applicable method for the study of phenyl radicals' reactions with neutral biomolecules in the gas phase is demonstrated. Neutral biomolecules were evaporated into a Fourier-transform ion cyclotron resonance mass spectrometer (FT-ICR) by means of laser-induced acoustic desorption (LIAD) and subsequently reacted with trapped charged phenyl radicals. The structural integrity of the evaporated alanylalanine molecules was verified by reaction with dichlorophosphenium ions. Examination of the reactions of charged phenyl radicals with alanylalanine and thymidine evaporated via LIAD revealed hydrogen atom abstraction for both alanylalanine and thymidine as well as an addition/elimination product for the reaction with thymidine. These reactions are consistent with the results obtained by others in solution. Further, a previously unstudied reaction of the nucleotide of thymine (T1) with charged phenyl radical was found to yield analogous products as the reaction with thymidine.

  14. THE LINE WIDTH DIFFERENCE OF NEUTRALS AND IONS INDUCED BY MHD TURBULENCE

    SciTech Connect

    Xu, Siyao; Lazarian, A.; Yan, Huirong

    2015-09-01

    We address the problem of the different line widths of coexistent neutrals and ions observed in molecular clouds and explore whether this difference can arise from the effects of magnetohydrodynamic (MHD) turbulence acting on partially ionized gas. Among the three fundamental modes of MHD turbulence, we find that fast and slow modes do not contribute to line width differences. We focus on the Alfvénic component, and consider the damping of Alfvén modes by taking into account both neutral-ion collisions and neutral viscosity. We confirm that the line width difference can be explained by the differential damping of the Alfvénic turbulence in ions and the hydrodynamic turbulence in neutrals, and find it strongly depends on the properties of MHD turbulence. We consider various regimes of turbulence corresponding to different media magnetizations and turbulent drivings. In the case of super-Alfvénic turbulence, when the damping scale of Alfvénic turbulence is below the Alfvénic scale l{sub A}, the line width difference does not depend on magnetic field strength. In other turbulence regimes, however, the dependence is present and evaluation of magnetic field from the observed line width difference is possible.

  15. Mode-conversion induced tearing effects in a plasma neutral sheet

    SciTech Connect

    Kaw, P.K.; Sudan, R.N.

    1981-01-01

    A new collisionless dissipation mechanism which can drive tearing modes in a plasma neutral sheet is described. The new mechanism relies on the presence of a background cold plasma which leads to mode conversion into a continuous spectrum of cold plasma waves.

  16. Immunization with a consensus epitope from Human Papillomavirus L2 induces antibodies that are broadly neutralizing

    PubMed Central

    Tyler, Mitchell; Tumban, Ebenezer; Dziduszko, Agnieszka; Ozbun, Michelle A.; Peabody, David S.; Chackerian, Bryce

    2014-01-01

    Vaccines targeting conserved epitopes in the HPV minor capsid protein, L2, can elicit antibodies that can protect against a broad spectrum of HPV types that are associated with cervical cancer and other HPV malignancies. Thus, L2 vaccines have been explored as alternatives to the current HPV vaccines, which are largely type-specific. In this study we assessed the immunogenicity of peptides spanning the N-terminal domain of L2 linked to the surface of a highly immunogenic bacteriophage virus-like particle (VLP) platform. Although all of the HPV16 L2 peptide-displaying VLPs elicited high-titer anti-peptide antibody responses, only a subset of the immunogens elicited antibody responses that were strongly protective from HPV16 pseudovirus (PsV) infection in a mouse genital challenge model. One of these peptides, mapping to HPV16 L2 amino acids 65–85, strongly neutralized HPV16 PsV but showed little ability to cross-neutralize other high-risk HPV types. In an attempt to broaden the protection generated through vaccination with this peptide, we immunized mice with VLPs displaying a peptide that represented a consensus sequence from high-risk and other HPV types. Vaccinated mice produced antibodies with broad, high-titer neutralizing activity against all of the HPV types that we tested. Therefore, immunization with virus-like particles displaying a consensus HPV sequence is an effective method to broaden neutralizing antibody responses against a type-specific epitope. PMID:24962748

  17. Neutralization of interleukin-17A delays progression of silica-induced lung inflammation and fibrosis in C57BL/6 mice.

    PubMed

    Chen, Ying; Li, Cuiying; Weng, Dong; Song, Laiyu; Tang, Wen; Dai, Wujing; Yu, Ye; Liu, Fangwei; Zhao, Ming; Lu, Chunwei; Chen, Jie

    2014-02-15

    Silica exposure can cause lung inflammation and fibrosis, known as silicosis. Interleukin-17A (IL-17A) and Th17 cells play a pivotal role in controlling inflammatory diseases. However, the roles of IL-17A and Th17 cells in the progress of silica-induced inflammation and fibrosis are poorly understood. This study explored the effects of IL-17A on silica-induced inflammation and fibrosis. We used an anti-mouse IL-17A antibody to establish an IL-17A-neutralized mice model, and mice were exposed to silica to establish an experimental silicosis model. We showed that IL-17A neutralization delayed neutrophil accumulation and progression of silica-induced lung inflammation and fibrosis. IL-17A neutralization reduced the percentage of Th17 in CD4+ T cells, decreased IL-6 and IL-1β expression, and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A delayed silica-induced Th1/Th2 immune and autoimmune responses. These results suggest that IL-17A neutralization alleviates early stage silica-induced lung inflammation and delays progression of silica-induced lung inflammation and fibrosis. Neutralization of IL-17A suppressed Th17 cell development by decreasing IL-6 and/or IL-1β and increased Tregs at an early phase of silica-induced inflammation. Neutralization of IL-17A also delayed the Th1/Th2 immune response during silica-induced lung inflammation and fibrosis. IL-17A may play a pivotal role in the early phase of silica-induced inflammation and may mediate the Th immune response to influence silica-induced lung inflammation and fibrosis in mice.

  18. Lack of LCAT reduces the LPS-neutralizing capacity of HDL and enhances LPS-induced inflammation in mice.

    PubMed

    Petropoulou, Peristera-Ioanna; Berbée, Jimmy F P; Theodoropoulos, Vassilios; Hatziri, Aikaterini; Stamou, Panagiota; Karavia, Eleni A; Spyridonidis, Alexandros; Karagiannides, Iordanes; Kypreos, Kyriakos E

    2015-10-01

    HDL has important immunomodulatory properties, including the attenuation of lipopolysaccharide (LPS)-induced inflammatory response. As lecithin-cholesterol acyltransferase (LCAT) is a critical enzyme in the maturation of HDL we investigated whether LCAT-deficient (Lcat(-/-)) mice present an increased LPS-induced inflammatory response. LPS (100μg/kg body weight)-induced cytokine response in Lcat(-/-) mice was markedly enhanced and prolonged compared to wild-type mice. Importantly, reintroducing LCAT expression using adenovirus-mediated gene transfer reverted their phenotype to that of wild-type mice. Ex vivo stimulation of whole blood with LPS (1-100ng/mL) showed a similar enhanced pro-inflammatory phenotype. Further characterization in RAW 264.7 macrophages in vitro showed that serum and HDL, but not chylomicrons, VLDL or the lipid-free protein fraction of Lcat(-/-) mice, had a reduced capacity to attenuate the LPS-induced TNFα response. Analysis of apolipoprotein composition revealed that LCAT-deficient HDL lacks significant amounts of ApoA-I and ApoA-II and is primarily composed of ApoE, while HDL from Apoa1(-/-) mice is highly enriched in ApoE and ApoA-II. ApoA-I-deficiency did not affect the capacity of HDL to neutralize LPS, though Apoa1(-/-) mice showed a pronounced LPS-induced cytokine response. Additional immunophenotyping showed that Lcat(-/-) , but not Apoa1(-/-) mice, have markedly increased circulating monocyte numbers as a result of increased Cd11b(+)Ly6C(med) monocytes, whereas 'pro-inflammatory' Cd11b(+)Ly6C(hi) monocytes were reduced. In line with this observation, peritoneal macrophages of Lcat(-/-) mice showed a markedly dampened LPS-induced TNFα response. We conclude that LCAT-deficiency increases LPS-induced inflammation in mice due to reduced LPS-neutralizing capacity of immature discoidal HDL and increased monocyte number. PMID:26170061

  19. Numerical validation of axial plasma momentum lost to a lateral wall induced by neutral depletion

    SciTech Connect

    Takao, Yoshinori; Takahashi, Kazunori

    2015-11-15

    Momentum imparted to a lateral wall of a compact inductively coupled plasma thruster is numerically investigated for argon and xenon gases by a particle-in-cell simulation with Monte Carlo collisions (PIC-MCC). Axial plasma momentum lost to a lateral wall is clearly shown when axial depletion of the neutrals is enhanced, which is in qualitative agreement with the result in a recent experiment using a helicon plasma source [Takahashi et al., Phys. Rev. Lett. 114, 195001 (2015)]. The PIC-MCC calculations demonstrate that the neutral depletion causes an axially asymmetric profile of the plasma density and potential, leading to axial ion acceleration and the non-negligible net axial force exerted to the lateral wall in the opposite direction of the thrust.

  20. Anti-idiotypic antibodies induce neutralizing antibodies to bovine herpesvirus 1.

    PubMed Central

    Srikumaran, S; Onisk, D V; Borca, M V; Nataraj, C; Zamb, T J

    1990-01-01

    A neutralizing murine monoclonal antibody (mAb) of the IgG2a isotype (MM-113), specific for bovine herpesvirus 1 (BHV-1) glycoprotein gIV, was used to develop anti-idiotypic antibodies (anti-Id) in a calf. The bovine anti-Id were isolated from the serum of the immunized calf by affinity chromatography on an MM-113-Sepharose column, followed by repeated adsorption on a murine IgG2a column. The anti-Id thus obtained specifically reacted with MM-113, but not with isotype-matched controls. They also inhibited the binding of MM-113 to BHV-1 in a concentration-dependent manner. Mice immunized with the anti-Id produced neutralizing antibodies to BHV-1. The anti-Id bound to cells permissive to BHV-1 in a cell-binding radioimmunoassay (RIA). PMID:2165998

  1. Charge neutrality of quasi-free-standing monolayer graphene induced by the intercalated Sn layer

    NASA Astrophysics Data System (ADS)

    Kim, Hidong; Dugerjav, Otgonbayar; Lkhagvasuren, Altaibaatar; Seo, Jae M.

    2016-04-01

    It has been confirmed by angle-resolved photoemission spectroscopy that decoupled quasi-free-standing monolayer graphene (QFMLG), obtained by Sn intercalation between the ≤ft(6\\sqrt{3}× 6\\sqrt{3}\\right)R{{30}{^\\circ}} buffer layer and the 6H-SiC(0 0 0 1) substrate, is charge-neutral, i.e. the Dirac point matches with the Fermi level. By combined studies of scanning tunneling microscopy/spectroscopy and core-level/valence-band photoemission spectroscopy on this system, it has been found that the intercalated Sn atoms, bonding with the Si atoms of the top Si-C bilayer on the substrate comprise a hexagonal 10× 10 layer, which turns out to be metallic. Such a metallic character, which has never been found in intercalation using different elements, is a major cause of charge neutrality of QFMLG, since conduction electrons of the Sn layer compensate completely spontaneous polarization charges of 6H-SiC(0 0 0 1). This charge-neutral QFMLG is stable at a high temperature of 850 °C.

  2. Vaccine-Induced Antibodies that Neutralize Group 1 and Group 2 Influenza A Viruses.

    PubMed

    Joyce, M Gordon; Wheatley, Adam K; Thomas, Paul V; Chuang, Gwo-Yu; Soto, Cinque; Bailer, Robert T; Druz, Aliaksandr; Georgiev, Ivelin S; Gillespie, Rebecca A; Kanekiyo, Masaru; Kong, Wing-Pui; Leung, Kwanyee; Narpala, Sandeep N; Prabhakaran, Madhu S; Yang, Eun Sung; Zhang, Baoshan; Zhang, Yi; Asokan, Mangaiarkarasi; Boyington, Jeffrey C; Bylund, Tatsiana; Darko, Sam; Lees, Christopher R; Ransier, Amy; Shen, Chen-Hsiang; Wang, Lingshu; Whittle, James R; Wu, Xueling; Yassine, Hadi M; Santos, Celia; Matsuoka, Yumiko; Tsybovsky, Yaroslav; Baxa, Ulrich; Mullikin, James C; Subbarao, Kanta; Douek, Daniel C; Graham, Barney S; Koup, Richard A; Ledgerwood, Julie E; Roederer, Mario; Shapiro, Lawrence; Kwong, Peter D; Mascola, John R; McDermott, Adrian B

    2016-07-28

    Antibodies capable of neutralizing divergent influenza A viruses could form the basis of a universal vaccine. Here, from subjects enrolled in an H5N1 DNA/MIV-prime-boost influenza vaccine trial, we sorted hemagglutinin cross-reactive memory B cells and identified three antibody classes, each capable of neutralizing diverse subtypes of group 1 and group 2 influenza A viruses. Co-crystal structures with hemagglutinin revealed that each class utilized characteristic germline genes and convergent sequence motifs to recognize overlapping epitopes in the hemagglutinin stem. All six analyzed subjects had sequences from at least one multidonor class, and-in half the subjects-multidonor-class sequences were recovered from >40% of cross-reactive B cells. By contrast, these multidonor-class sequences were rare in published antibody datasets. Vaccination with a divergent hemagglutinin can thus increase the frequency of B cells encoding broad influenza A-neutralizing antibodies. We propose the sequence signature-quantified prevalence of these B cells as a metric to guide universal influenza A immunization strategies.

  3. Vaccine-Induced Antibodies that Neutralize Group 1 and Group 2 Influenza A Viruses.

    PubMed

    Joyce, M Gordon; Wheatley, Adam K; Thomas, Paul V; Chuang, Gwo-Yu; Soto, Cinque; Bailer, Robert T; Druz, Aliaksandr; Georgiev, Ivelin S; Gillespie, Rebecca A; Kanekiyo, Masaru; Kong, Wing-Pui; Leung, Kwanyee; Narpala, Sandeep N; Prabhakaran, Madhu S; Yang, Eun Sung; Zhang, Baoshan; Zhang, Yi; Asokan, Mangaiarkarasi; Boyington, Jeffrey C; Bylund, Tatsiana; Darko, Sam; Lees, Christopher R; Ransier, Amy; Shen, Chen-Hsiang; Wang, Lingshu; Whittle, James R; Wu, Xueling; Yassine, Hadi M; Santos, Celia; Matsuoka, Yumiko; Tsybovsky, Yaroslav; Baxa, Ulrich; Mullikin, James C; Subbarao, Kanta; Douek, Daniel C; Graham, Barney S; Koup, Richard A; Ledgerwood, Julie E; Roederer, Mario; Shapiro, Lawrence; Kwong, Peter D; Mascola, John R; McDermott, Adrian B

    2016-07-28

    Antibodies capable of neutralizing divergent influenza A viruses could form the basis of a universal vaccine. Here, from subjects enrolled in an H5N1 DNA/MIV-prime-boost influenza vaccine trial, we sorted hemagglutinin cross-reactive memory B cells and identified three antibody classes, each capable of neutralizing diverse subtypes of group 1 and group 2 influenza A viruses. Co-crystal structures with hemagglutinin revealed that each class utilized characteristic germline genes and convergent sequence motifs to recognize overlapping epitopes in the hemagglutinin stem. All six analyzed subjects had sequences from at least one multidonor class, and-in half the subjects-multidonor-class sequences were recovered from >40% of cross-reactive B cells. By contrast, these multidonor-class sequences were rare in published antibody datasets. Vaccination with a divergent hemagglutinin can thus increase the frequency of B cells encoding broad influenza A-neutralizing antibodies. We propose the sequence signature-quantified prevalence of these B cells as a metric to guide universal influenza A immunization strategies. PMID:27453470

  4. HYDROCEPHALUS IN THREE JUVENILE NORTH AMERICAN BLACK BEARS (URSUS AMERICANUS).

    PubMed

    Ferguson, Sylvia H; Novak, Janelle; Hecht, Silke; Craig, Linden E

    2016-06-01

    Hydrocephalus has been reported in a variety of species, including the North American black bear ( Ursus americanus ). This report describes three cases of hydrocephalus in this species from wild bears aged 3-4 mo considered retrospectively from necropsy records of one institution. Clinical signs included cortical blindness and ataxia. Primary gross findings were doming of the skull, gyri compression and flattening, and lateral ventricle dilation. Two cases had severe bilateral ventricular dilation with loss of the septum pellucidum; atrophy of the surrounding corpus callosum; and bilateral periventricular tears involving the caudate nuclei, internal capsule, and adjacent cerebrum. Histologically, the cases with periventricular tearing had severe axonal loss and degeneration, malacia, hemorrhage, and variable periventricular astrocytosis. All cases were likely congenital, given the bears' age and lack of an apparent acquired obstruction. PMID:27468040

  5. Tetranucleotide microsatellite loci from the black bear (Ursus americanus)

    USGS Publications Warehouse

    Sanderlin, J.S.; Faircloth, B.C.; Shamblin, B.; Conroy, M.J.

    2009-01-01

    We describe primers and polymerase chain reaction conditions to amplify 21 tetranucleotide microsatellite DNA loci in black bears (Ursus americanus). We tested primers using individuals from two populations, one each in Georgia and Florida. Among individuals from Georgia (n = 29), primer pairs yielded an average of 2.9 alleles (range, one to four) and an average observed heterozygosity (HO) of 0.50 (range, 0.00 to 0.79). Among individuals from Florida (n = 19), primer pairs yielded an average of 5.7 alleles (range, one to 14) and an HO of 0.55 (range, 0.00 to 1.00). A comparison of previously developed markers with individuals from Georgia suggests that bear populations in Georgia and Florida have reduced allelic diversity relative to other populations. ?? 2008 The Authors.

  6. HYDROCEPHALUS IN THREE JUVENILE NORTH AMERICAN BLACK BEARS (URSUS AMERICANUS).

    PubMed

    Ferguson, Sylvia H; Novak, Janelle; Hecht, Silke; Craig, Linden E

    2016-06-01

    Hydrocephalus has been reported in a variety of species, including the North American black bear ( Ursus americanus ). This report describes three cases of hydrocephalus in this species from wild bears aged 3-4 mo considered retrospectively from necropsy records of one institution. Clinical signs included cortical blindness and ataxia. Primary gross findings were doming of the skull, gyri compression and flattening, and lateral ventricle dilation. Two cases had severe bilateral ventricular dilation with loss of the septum pellucidum; atrophy of the surrounding corpus callosum; and bilateral periventricular tears involving the caudate nuclei, internal capsule, and adjacent cerebrum. Histologically, the cases with periventricular tearing had severe axonal loss and degeneration, malacia, hemorrhage, and variable periventricular astrocytosis. All cases were likely congenital, given the bears' age and lack of an apparent acquired obstruction.

  7. Neutralization of Japanese Encephalitis Virus by heme-induced broadly reactive human monoclonal antibody

    PubMed Central

    Gupta, Nimesh; de Wispelaere, Mélissanne; Lecerf, Maxime; Kalia, Manjula; Scheel, Tobias; Vrati, Sudhanshu; Berek, Claudia; Kaveri, Srinivas V.; Desprès, Philippe; Lacroix-Desmazes, Sébastien; Dimitrov, Jordan D.

    2015-01-01

    Geographical expansion and re-emerging new genotypes of the Japanese encephalitis virus (JEV) require the development of novel therapeutic approaches. Here, we studied a non-conventional approach for antibody therapy and show that, upon exposure to heme, a fraction of natural human immunoglobulins acquires high-affinity reactivity with the antigenic domain-III of JEV E glycoprotein. These JEV-reactive antibodies exhibited neutralizing activity against recently dominant JEV genotypes. This study opens new therapeutic options for Japanese encephalitis. PMID:26542535

  8. Neutralization of Japanese Encephalitis Virus by heme-induced broadly reactive human monoclonal antibody.

    PubMed

    Gupta, Nimesh; de Wispelaere, Mélissanne; Lecerf, Maxime; Kalia, Manjula; Scheel, Tobias; Vrati, Sudhanshu; Berek, Claudia; Kaveri, Srinivas V; Desprès, Philippe; Lacroix-Desmazes, Sébastien; Dimitrov, Jordan D

    2015-01-01

    Geographical expansion and re-emerging new genotypes of the Japanese encephalitis virus (JEV) require the development of novel therapeutic approaches. Here, we studied a non-conventional approach for antibody therapy and show that, upon exposure to heme, a fraction of natural human immunoglobulins acquires high-affinity reactivity with the antigenic domain-III of JEV E glycoprotein. These JEV-reactive antibodies exhibited neutralizing activity against recently dominant JEV genotypes. This study opens new therapeutic options for Japanese encephalitis. PMID:26542535

  9. DCP-LA neutralizes mutant amyloid beta peptide-induced impairment of long-term potentiation and spatial learning.

    PubMed

    Nagata, Tetsu; Tomiyama, Takami; Tominaga, Takemi; Mori, Hiroshi; Yaguchi, Takahiro; Nishizaki, Tomoyuki

    2010-01-01

    Long-term potentiation (LTP) was monitored from the CA1 region of the intact rat hippocampus by delivering high frequency stimulation (HFS) to the Schaffer collateral commissural pathway. Intraventricular injection with mutant amyloid beta(1-42) peptide lacking glutamate-22 (Abeta(1-42)E22Delta), favoring oligomerization, 10 min prior to HFS, inhibited expression of LTP, with the potency more than wild-type amyloid beta(1-42) peptide. Intraperitoneal injection with the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid (DCP-LA) 70 min prior to HFS neutralized mutant Abeta(1-42)E22Delta peptide-induced LTP inhibition. In the water maze test, continuous intraventricular injection with mutant Abeta(1-42)E22Delta peptide for 14 days prolonged the acquisition latency as compared with that for control, with the potency similar to wild-type Abeta(1-42) peptide, and intraperitoneal injection with DCP-LA shortened the prolonged latency to control levels. The results of the present study indicate that DCP-LA neutralizes mutant Abeta(1-42)E22Delta peptide-induced impairment of LTP and spatial learning.

  10. Maturation-Induced Cloaking of Neutralization Epitopes on HIV-1 Particles

    PubMed Central

    Joyner, Amanda S.; Willis, Jordan R.; Crowe, James E.; Aiken, Christopher

    2011-01-01

    To become infectious, HIV-1 particles undergo a maturation process involving proteolytic cleavage of the Gag and Gag-Pol polyproteins. Immature particles contain a highly stable spherical Gag lattice and are impaired for fusion with target cells. The fusion impairment is relieved by truncation of the gp41 cytoplasmic tail (CT), indicating that an interaction between the immature viral core and gp41 within the particle represses HIV-1 fusion by an unknown mechanism. We hypothesized that the conformation of Env on the viral surface is regulated allosterically by interactions with the HIV-1 core during particle maturation. To test this, we quantified the binding of a panel of monoclonal antibodies to mature and immature HIV-1 particles by immunofluorescence imaging. Surprisingly, immature particles exhibited markedly enhanced binding of several gp41-specific antibodies, including two that recognize the membrane proximal external region (MPER) and neutralize diverse HIV-1 strains. Several of the differences in epitope exposure on mature and immature particles were abolished by truncation of the gp41 CT, thus linking the immature HIV-1 fusion defect with altered Env conformation. Our results suggest that perturbation of fusion-dependent Env conformational changes contributes to the impaired fusion of immature particles. Masking of neutralization-sensitive epitopes during particle maturation may contribute to HIV-1 immune evasion and has practical implications for vaccine strategies targeting the gp41 MPER. PMID:21931551

  11. Stress-induced neutral lipid biosynthesis in microalgae - Molecular, cellular and physiological insights.

    PubMed

    Zienkiewicz, Krzysztof; Du, Zhi-Yan; Ma, Wei; Vollheyde, Katharina; Benning, Christoph

    2016-09-01

    Photosynthetic microalgae have promise as biofuel feedstock. Under certain conditions, they produce substantial amounts of neutral lipids, mainly in the form of triacylglycerols (TAGs), which can be converted to fuels. Much of our current knowledge on the genetic and molecular basis of algal neutral lipid metabolism derives mainly from studies of plants, i.e. seed tissues, and to a lesser extent from direct studies of algal lipid metabolism. Thus, the knowledge of TAG synthesis and the cellular trafficking of TAG precursors in algal cells is to a large extent based on genome predictions, and most aspects of TAG metabolism have yet to be experimentally verified. The biofuel prospects of microalgae have raised the interest in mechanistic studies of algal TAG biosynthesis in recent years and resulted in an increasing number of publications on lipid metabolism in microalgae. In this review we summarize the current findings on genetic, molecular and physiological studies of TAG accumulation in microalgae. Special emphasis is on the functional analysis of key genes involved in TAG synthesis, molecular mechanisms of regulation of TAG biosynthesis, as well as on possible mechanisms of lipid droplet formation in microalgal cells. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner. PMID:26883557

  12. Molecular immune response of the American lobster (Homarus americanus) to the White Spot Syndrome Virus.

    PubMed

    Clark, K Fraser; Greenwood, Spencer J; Acorn, Adam R; Byrne, Philip J

    2013-11-01

    The adult American lobster (Homarus americanus) is susceptible to few naturally occurring pathogens, and no viral pathogen is known to exist. Despite this, relatively little is known about the H. americanus immune system and nothing is known about its potential viral immune response. Hundreds of rural communities in Atlantic Canada rely on the lobster fishery for their economic sustainability and could be devastated by large-scale pathogen-mediated mortality events. The White Spot Syndrome Virus is the most economically devastating viral pathogen to global shrimp aquaculture production and has been proposed to be capable of infecting all decapod crustaceans including the European Lobster. An in vivo WSSV injection challenge was conducted in H. americanus and WSSV was found to be capable of infecting and replicating within lobsters held at 20°C. The in vivo WSSV challenge also generated the first viral disease model of H. americanus and allowed for the high-throughput examination of transcriptomic changes that occur during viral infection. Microarray analysis found 136 differentially expressed genes and the expression of a subset of these genes was verified using RT-qPCR. Anti-lipopolysaccharide isoforms and acute phase serum amyloid protein A expression did not change during WSSV infection, contrary to previous findings during bacterial and parasitic infection of H. americanus. This, along with the differential gene expression of thioredoxin and trypsin isoforms, provides compelling evidence that H. americanus is capable of mounting an immune response specific to infection by different pathogen classes.

  13. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    SciTech Connect

    Alvarez-Ruso, L.; Nieves, J.; Wang, E.

    2015-10-15

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed.

  14. Single photon production induced by (anti)neutrino neutral current scattering on nucleons and nuclear targets

    NASA Astrophysics Data System (ADS)

    Alvarez-Ruso, L.; Nieves, J.; Wang, E.

    2015-10-01

    We review our theoretical approach to neutral current photon emission on nucleons and nuclei in the few-GeV energy region, relevant for neutrino oscillation experiments. These reactions are dominated by the weak excitation of the Δ(1232) resonance but there are also important non-resonant contributions. We have also included terms mediated by nucleon excitations from the second resonance region. On nuclei, Pauli blocking, Fermi motion and the in-medium Δ resonance broadening have been taken into account for both incoherent and coherent reaction channels. With this model, the number and distributions of photon events at the MiniBooNE and T2K experiments have been obtained. We have also compared to the NOMAD upper limit at higher energies. The implications of our findings and future perspectives are discussed.

  15. Induced conformational change in human IL‐4 upon binding of a signal‐neutralizing DARPin

    PubMed Central

    Teplyakov, Alexey; Malia, Thomas J.; Keough, Edward; Luo, Jinquan; Sweet, Raymond; Jacobs, Steven A.; Yi, Fang; Hippensteel, Randi; O'Neil, Karyn T.

    2015-01-01

    ABSTRACT The crystal structure of DARPin 44C12V5 that neutralizes IL‐4 signaling has been determined alone and bound to human IL‐4. A significant conformational change occurs in the IL‐4 upon DARPin binding. The DARPin binds to the face of IL‐4 formed by the A and C α‐helices. The structure of the DARPin remains virtually unchanged. The conformational changes in IL‐4 include a reorientation of the C‐helix Trp91 side chain and repositioning of CD‐loop residue Leu96. Both side chains move by >9 Å, becoming buried in the central hydrophobic region of the IL‐4:DARPin interface. This hydrophobic region is surrounded by a ring of hydrophilic interactions comprised of hydrogen bonds and salt bridges and represents a classical “hotspot.” The structures also reveal how the DARPin neutralizes IL‐4 signaling. Comparing the IL‐4:DARPin complex structure with the structures of IL‐4 bound to its receptors (Hage et al., Cell 1999; 97, 271‐281; La Porte et al., Cell 2008, 132, 259‐272), it is found that the DARPin binds to the same IL‐4 face that interacts with the junction of the D1 and D2 domains of the IL‐4Rα receptors. Signaling is blocked since IL‐4 cannot bind to this receptor, which it must do first before initiating a productive receptor complex with either the IL‐13α1 or the γ c receptor. Proteins 2015; 83:1191–1197. © 2015 The Authors. Proteins: Structure, Function, and Bioinformatics Published by Wiley Periodicals, Inc. PMID:25900776

  16. Recombinant outer membrane vesicles carrying Chlamydia muridarum HtrA induce antibodies that neutralize chlamydial infection in vitro

    PubMed Central

    Bartolini, Erika; Ianni, Elvira; Frigimelica, Elisabetta; Petracca, Roberto; Galli, Giuliano; Berlanda Scorza, Francesco; Norais, Nathalie; Laera, Donatello; Giusti, Fabiola; Pierleoni, Andrea; Donati, Manuela; Cevenini, Roberto; Finco, Oretta; Grandi, Guido; Grifantini, Renata

    2013-01-01

    Background Outer membrane vesicles (OMVs) are spheroid particles released by all Gram-negative bacteria as a result of the budding out of the outer membrane. Since they carry many of the bacterial surface-associated proteins and feature a potent built-in adjuvanticity, OMVs are being utilized as vaccines, some of which commercially available. Recently, methods for manipulating the protein content of OMVs have been proposed, thus making OMVs a promising platform for recombinant, multivalent vaccines development. Methods Chlamydia muridarum DO serine protease HtrA, an antigen which stimulates strong humoral and cellular responses in mice and humans, was expressed in Escherichia coli fused to the OmpA leader sequence to deliver it to the OMV compartment. Purified OMVs carrying HtrA (CM rHtrA-OMV) were analyzed for their capacity to induce antibodies capable of neutralizing Chlamydia infection of LLC-MK2 cells in vitro. Results CM rHtrA-OMV immunization in mice induced antibodies that neutralize Chlamydial invasion as judged by an in vitro infectivity assay. This was remarkably different from what observed with an enzymatically functional recombinant HtrA expressed in, and purified from the E. coli cytoplasm (CM rHtrA). The difference in functionality between anti-CM rHtrA and anti-CM rHtrA-OMV antibodies was associated to a different pattern of protein epitopes recognition. The epitope recognition profile of anti-CM HtrA-OMV antibodies was similar to that induced in mice during Chlamydial infection. Conclusions When expressed in OMVs HtrA appears to assume a conformation similar to the native one and this results in the elicitation of functional immune responses. These data further support the potentiality of OMVs as vaccine platform. PMID:24009891

  17. Diffuse traumatic axonal injury in mice induces complex behavioural alterations that are normalized by neutralization of interleukin-1β.

    PubMed

    Ekmark-Lewén, Sara; Flygt, Johanna; Fridgeirsdottir, Gudrun A; Kiwanuka, Olivia; Hånell, Anders; Meyerson, Bengt J; Mir, Anis K; Gram, Hermann; Lewén, Anders; Clausen, Fredrik; Hillered, Lars; Marklund, Niklas

    2016-04-01

    Widespread traumatic axonal injury (TAI) results in brain network dysfunction, which commonly leads to persisting cognitive and behavioural impairments following traumatic brain injury (TBI). TBI induces a complex neuroinflammatory response, frequently located at sites of axonal pathology. The role of the pro-inflammatory cytokine interleukin (IL)-1β has not been established in TAI. An IL-1β-neutralizing or a control antibody was administered intraperitoneally at 30 min following central fluid percussion injury (cFPI), a mouse model of widespread TAI. Mice subjected to moderate cFPI (n = 41) were compared with sham-injured controls (n = 20) and untreated, naive mice (n = 9). The anti-IL-1β antibody reached the target brain regions in adequate therapeutic concentrations (up to ~30 μg/brain tissue) at 24 h post-injury in both cFPI (n = 5) and sham-injured (n = 3) mice, with lower concentrations at 72 h post-injury (up to ~18 μg/g brain tissue in three cFPI mice). Functional outcome was analysed with the multivariate concentric square field (MCSF) test at 2 and 9 days post-injury, and the Morris water maze (MWM) at 14-21 days post-injury. Following TAI, the IL-1β-neutralizing antibody resulted in an improved behavioural outcome, including normalized behavioural profiles in the MCSF test. The performance in the MWM probe (memory) trial was improved, although not in the learning trials. The IL-1β-neutralizing treatment did not influence cerebral ventricle size or the number of microglia/macrophages. These findings support the hypothesis that IL-1β is an important contributor to the processes causing complex cognitive and behavioural disturbances following TAI.

  18. Variable epitope libraries: new vaccine immunogens capable of inducing broad human immunodeficiency virus type 1-neutralizing antibody response.

    PubMed

    Charles-Niño, Claudia; Pedroza-Roldan, Cesar; Viveros, Monica; Gevorkian, Goar; Manoutcharian, Karen

    2011-07-18

    The extreme antigenic variability of human immunodeficiency virus (HIV) leads to immune escape of the virus, representing a major challenge in the design of effective vaccine. We have developed a novel concept for immunogen construction based on introduction of massive mutations within the epitopes targeting antigenically variable pathogens and diseases. Previously, we showed that these immunogens carrying large combinatorial libraries of mutated epitope variants, termed as variable epitope libraries (VELs), induce potent, broad and long lasting CD8+IFN-γ+ T-cell response. Moreover, we demonstrated that these T cells recognize more than 50% of heavily mutated variants (5 out of 10 amino acid positions were mutated in each epitope variant) of HIV-1 gp120 V3 loop-derived cytotoxic T lymphocyte epitope (RGPGRAFVTI) in mice. The constructed VELs had complexities of 10000 and 12500 individual members, generated as plasmid DNA or as M13 phage display combinatorial libraries, respectively, and with structural composition RGPGXAXXXX or XGXGXAXVXI, where X is any of 20 natural amino acids. Here, we demonstrated that sera from mice immunized with these VELs are capable of neutralizing 5 out of 10 viral isolates from Tier 2 reference panel of subtype B envelope clones, including HIV-1 isolates which are known to be resistant to neutralization by several potent monoclonal antibodies, described previously. These data indicate the feasibility of the application of immunogens based on VEL concept as an alternative approach for the development of molecular vaccines against antigenically variable pathogens.

  19. Neutral endopeptidase regulates neurogenic inflammatory responses induced by stimulation of human oral keratinocytes with bacterial lipopolysaccharide and nicotine.

    PubMed

    Nakata, Motoki; Awano, Shuji; Kinoshita, Naomasa; Yoshida, Akihiro; Ansai, Toshihiro

    2013-10-01

    Neutral endopeptidase (NEP) is present on various epithelial cells and inactivates numerous physiologically active peptides. Neutral endopeptidase may regulate proinflammatory signals in oral mucosal epithelium. However, the function of NEP in oral mucosal epithelium is unknown. The present study investigated the action of NEP upon proinflammatory signals on human oral keratinocytes and the influence of endothelin-converting enzyme (ECE)-1, an enzyme similar to NEP, on the functions of NEP. Oral keratinocytes were cultured in medium containing inflammatory inducers [lipopolysaccharide (LPS) and nicotine], NEP inhibitors, and ECE-1/NEP inhibitors, either alone or in combination. The concentrations of substance P (SP) and interleukin-1β (IL-1β) were measured in the supernatant. Additionally, the concentrations of SP and IL-1β were measured in the supernatant of cells incubated with LPS or nicotine after transfection with NEP small interfering RNA (siRNA). The concentrations of SP and IL-1β were significantly increased in cells incubated with NEP inhibitors and, to a lesser extent, in cells incubated with ECE-1/NEP inhibitors, compared with controls (cells incubated with LPS or nicotine alone). The concentrations of SP and IL-1β in cells transfected with NEP siRNA were significantly augmented compared with controls. In conclusion, the present study demonstrated that NEP down-regulated the levels of SP and IL-1β produced from human oral keratinocytes, although ECE-1 may be partly related to the down-regulation.

  20. Time-resolved imaging of laser-induced vibrational wave packets in neutral and ionic states of iodomethane

    NASA Astrophysics Data System (ADS)

    Malakar, Y.; Kaderiya, B.; Zohrabi, M.; Pearson, W. L.; Ziaee, F.; Kananka Raju, P.; Ben-Itzhak, I.; Rolles, D.; Rudenko, A.

    2016-05-01

    Light-driven vibrational wave packets play an important role in molecular imaging and coherent control applications. Here we present the results of a pump-probe experiment characterizing laser-induced vibrational wave packets in both, neutral and ionic states of CH3 I (iodomethane), one of the prototypical polyatomic systems. Measuring yields and kinetic energies of all ionic fragments as a function of the time delay between two 25 fs, 800 nm pump and probe pulses, we map vibrational motion of the molecule, and identify the states involved by channel-resolved Fourier spectroscopy. In the Coulomb explosion channels we observe features with ~ 130 fs periodicity resulting from C-I symmetric stretch (ν3 mode) of the electronically excited cationic state. However the Fourier transform of the low-energy I+ ion yield produced by the dissociative ionization of CH3 I reveals the signatures of the same vibrational mode in the ground electronic states of both, neutral and cation, reflected in 65-70 fs oscillations. We observe the degeneration of the oscillatory structures from the cationic states within ~ 2 ps and discuss most likely reasons for this behavior. Supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U. S. DOE. K. R. P. and W. L. P. supported by NSF Award No. IIA-143049.

  1. Env-Expressing Autologous T Lymphocytes Induce Neutralizing Antibody and Afford Marked Protection against Feline Immunodeficiency Virus ▿

    PubMed Central

    Pistello, Mauro; Bonci, Francesca; Zabogli, Elisa; Conti, Francesca; Freer, Giulia; Maggi, Fabrizio; Stevenson, Mario; Bendinelli, Mauro

    2010-01-01

    The envelope (Env) glycoproteins of HIV and other lentiviruses possess neutralization and other protective epitopes, yet all attempts to induce protective immunity using Env as the only immunogen have either failed or afforded minimal levels of protection. In a novel prime-boost approach, specific-pathogen-free cats were primed with a plasmid expressing Env of feline immunodeficiency virus (FIV) and feline granulocyte-macrophage colony-stimulating factor and then boosted with their own T lymphocytes transduced ex vivo to produce the same Env and interleukin 15 (3 × 106 to 10 × 106 viable cells/cat). After the boost, the vaccinees developed elevated immune responses, including virus-neutralizing antibodies (NA). Challenge with an ex vivo preparation of FIV readily infected all eight control cats (four mock vaccinated and four naïve) and produced a marked decline in the proportion of peripheral CD4 T cells. In contrast, five of seven vaccinees showed little or no traces of infection, and the remaining two had reduced viral loads and underwent no changes in proportions of CD4 T cells. Interestingly, the viral loads of the vaccinees were inversely correlated to the titers of NA. The findings support the concept that Env is a valuable immunogen but needs to be administered in a way that permits the expression of its full protective potential. PMID:20130057

  2. Analysis of gene expression in Homarus americanus larvae exposed to sublethal concentrations of endosulfan during metamorphosis.

    PubMed

    Bauer, Megan; Greenwood, Spencer J; Clark, K Fraser; Jackman, Paula; Fairchild, Wayne

    2013-12-01

    Agricultural pesticide runoff has been suspected as the cause of numerous fish kills in rivers throughout Prince Edward Island but the impact on the surrounding marine environment is unknown. Endosulfan, an organochlorine pesticide, is a potent neurotoxin and molt inhibitor used to combat the Colorado potato beetle however it has the potential to affect non-target organisms including the American lobster (Homarus americanus). Metamorphosis is a critical stage of development and the effects of contaminant exposure during this time are largely unknown in lobster. A 14day endosulfan exposure was performed to identify the effects on survival, development and gene expression in lobster larvae during metamorphosis; all of which were predicted to be negatively impacted. The higher endosulfan concentrations resulted in greater mortality and a significant increase in the number of days required to reach metamorphosis in surviving animals. A custom made H. americanus microarray was used for monitoring the changes in expression of 14,592 genes at the termination of the exposure. Genes with >1.5 fold change and identified as being significant at p<0.05 using one-way ANOVA were selected for further analysis. A total of 707 genes were identified as being significantly differentiated, however with only ~40% annotation of the array, the majority of these genes were unknown. Annotated genes of interest were involved in many processes: development, metabolism, immunity and oxidative stress response and gene regulation. Nine genes of interest (histone H1, farnesoic acid O-methyltransferase, cuticle protein, glutathione S-transferase, thioredoxin, NADH dehydrogenase, ecdysone nuclear receptor Fushi tarazu F1 (FTZ-F1), ferritin and ecdysone inducible protein E75 (EIP-E75)) were selected for RT-qPCR validation of the microarray results. The RT-qPCR method was more sensitive than the microarray yet detected similar expression patterns. The two highest endosulfan concentrations resulted

  3. Analysis of gene expression in Homarus americanus larvae exposed to sublethal concentrations of endosulfan during metamorphosis.

    PubMed

    Bauer, Megan; Greenwood, Spencer J; Clark, K Fraser; Jackman, Paula; Fairchild, Wayne

    2013-12-01

    Agricultural pesticide runoff has been suspected as the cause of numerous fish kills in rivers throughout Prince Edward Island but the impact on the surrounding marine environment is unknown. Endosulfan, an organochlorine pesticide, is a potent neurotoxin and molt inhibitor used to combat the Colorado potato beetle however it has the potential to affect non-target organisms including the American lobster (Homarus americanus). Metamorphosis is a critical stage of development and the effects of contaminant exposure during this time are largely unknown in lobster. A 14day endosulfan exposure was performed to identify the effects on survival, development and gene expression in lobster larvae during metamorphosis; all of which were predicted to be negatively impacted. The higher endosulfan concentrations resulted in greater mortality and a significant increase in the number of days required to reach metamorphosis in surviving animals. A custom made H. americanus microarray was used for monitoring the changes in expression of 14,592 genes at the termination of the exposure. Genes with >1.5 fold change and identified as being significant at p<0.05 using one-way ANOVA were selected for further analysis. A total of 707 genes were identified as being significantly differentiated, however with only ~40% annotation of the array, the majority of these genes were unknown. Annotated genes of interest were involved in many processes: development, metabolism, immunity and oxidative stress response and gene regulation. Nine genes of interest (histone H1, farnesoic acid O-methyltransferase, cuticle protein, glutathione S-transferase, thioredoxin, NADH dehydrogenase, ecdysone nuclear receptor Fushi tarazu F1 (FTZ-F1), ferritin and ecdysone inducible protein E75 (EIP-E75)) were selected for RT-qPCR validation of the microarray results. The RT-qPCR method was more sensitive than the microarray yet detected similar expression patterns. The two highest endosulfan concentrations resulted

  4. Heat shock protein-70 neutralizes apoptosis inducing factor in Bcr/Abl expressing cells.

    PubMed

    Wang, Fang; Dai, An-Ya; Tao, Kun; Xiao, Qing; Huang, Zheng-Lan; Gao, Miao; Li, Hui; Wang, Xin; Cao, Wei-Xi; Feng, Wen-Li

    2015-10-01

    Bcr/Abl fusion protein is a hallmark of human chronic myeloid leukemia (CML). The protein can activate various signaling pathways to make normal cells transform malignantly and thus to facilitate tumorigenesis. It has been reported that heat shock protein-70 (HSP-70) can be served as an anti-apoptotic protein that suppresses Bax and Apo-2L/TRAIL. But it is unclear whether HSP-70 affects AIF-initiated apoptosis in Bcr/Abl expressing cells considering that HSP-70 is coincidentally over-regulated in these cells. Our findings supported that abundant HSP-70 in Bcr/Abl cells neutralizes AIF by segregating it from nucleus via direct interaction, leading to the failure of AIF initiating cell death and the silence of caspase-independent apoptotic pathway upon apoptotic induction. Moderate inhibition of HSP-70 expression by siRNA leads to Vp-16 triggered re-distribution of AIF in nucleus. In addition, AIF bears a HSP-70 binding domain allowing association with HSP-70. Therefore, disruption of the association using an AIF mutant lacking this domain can restore the potential of AIF importing into nucleus, and finally triggers cell death in a time dependent manner.

  5. Structural characterization of a novel neutral polysaccharide from Lentinus giganteus and its antitumor activity through inducing apoptosis.

    PubMed

    Tian, Yuting; Zhao, Yingting; Zeng, Hongliang; Zhang, Yaling; Zheng, Baodong

    2016-12-10

    A novel neutral polysaccharide (LGPS-1), with a molecular weight of 1.547×10(5)Da, was isolated from Lentinus giganteus by precipitation and purification. The monosaccharides included d-mannose (Man), d-glucose (Glc) and d-galactose (Gal) with a molar ratio of 3.0:4.1:7.1. The backbone of LGPS-1 was composed of 1,6-Galp and 1,3,6-Manp whereas the branches were composed of 1,6-Glcp and 1-Glcp. The anticancer efficacy of LGPS-1 was assessed using HepG2 hepatocellular carcinoma cells. The results showed that LGPS-1 inhibited the proliferation of HepG2 cells and also induced the activation of caspase-3, and cleavage of PARP-1. Western blot analysis revealed that LGSP-1 significantly induced a loss of mitochondrial membrane potential (Δym), increased the ratio of Bax/Bcl-2, promoted the release of cytochrome c into cytoplasm as well as inhibited the phosphorylation of Akt in HepG2 cells. These findings suggest that LGPS-1 induced apoptosis in HepG2 cells through intrinsic mitochondrial apoptosis and PI3K/Akt signaling pathways. PMID:27577914

  6. Predator prey size relationship between Pseudopleuronectes americanus and Carcinus maenas

    NASA Astrophysics Data System (ADS)

    Fairchild, E. A.; Howell, W. H.

    2000-10-01

    Young-of-year flatfish grow through a series of critical periods in which they are vulnerable to different predators, including decapod crustaceans. The purpose of this study was to determine if winter flounder, Pseudopleuronectes americanus, were vulnerable to one such decapod, the green crab, Carcinus maenas, and to determine if vulnerability differed between wild and cultured fish. To examine the predator-prey size relationship, an experiment was conducted in which six cultured and three wild winter flounder size class treatments were tested against six crab size class treatments. Flounder of all size classes were preyed on by all size classes of green crabs; however, mortality was highest when the largest crabs were matched with the smallest flounder. The number of flounder killed per day was significantly higher (31%) in winter flounder <20 mm compared to all other larger fish size classes (4-8%). Additionally, these fish were attacked at a faster rate than any other fish size class. For the 31-60 mm fish size classes tested, more wild fish (11%) were killed per day by crabs than cultured fish (6.3%). These results suggest that in a winter flounder stock enhancement program, only fish >20 mm should be released to promote post-release survival.

  7. Subcuticular urate accumulation in an American lobster (Homarus americanus).

    PubMed

    Battison, A L

    2013-05-01

    An unusually "lumpy" lobster, Homarus americanus, was presented to the Atlantic Veterinary College Lobster Science Centre for evaluation. The lobster was weak with numerous pale, raised, and flat areas (diameter, 3-15 mm) on the exoskeleton, some of which were ulcerated. On postmortem examination, the pale areas corresponded to accumulations of viscous to free-flowing white material, which was found in only the subcuticular connective tissues. No internal organs were affected. Direct light examination of nonstained impression smears of the material showed abundant crystals resembling uric acid, amorphous urates, and sodium urate, which were readily soluble in 1 M potassium hydroxide. Wright-Giemsa stained imprints showed numerous fine, rounded, nonstaining granules free in the background and within individual round cells. Fourier-transformed infrared spectroscopy confirmed the presence of urates or mixed urate salts. Hemolymph plasma urea (1.7 mmol/liter) and uric acid (287 μmol/liter) concentrations were slightly higher than those seen with 36-hour emersion. Histologic sections showed aggregates of vacuolated mononuclear cells in the loose subcuticular connective tissue occasionally infiltrating between underlying muscle fibers. Grossly visible urate deposits are occasionally documented in land crabs and rarely reported in the blue crab; none, however, are associated with deformation of the cuticle. Possible etiologies include increased uric acid intake or production or decreased excretion. Anecdotal reports of similarly affected lobsters have been received but are intermittent and undocumented.

  8. Spatial memory in captive American black bears (Ursus americanus).

    PubMed

    Zamisch, Valeria; Vonk, Jennifer

    2012-11-01

    The spatial memory and foraging strategies of four adult captive-born American black bears (Ursus americanus) were explored in four experiments using a simulated foraging task. In the first three experiments, each session consisted of two phases separated by a delay: During the exploration phase, subjects foraged among a set of baited and unbaited sites. During the delay, the same locations were rebaited and subjects were released again and allowed to search the sites (search phase). In Experiments 1a and 1b, different sites were baited each day and the interval between exploration and search was short (4 hr or 15 min). Subjects were not accurate at recovering the food items in either experiment. In Experiment 2, an "informed forager" paradigm was used in which one subject was given privileged knowledge about the location of the food during the exploration phase and was later released with an "uninformed" competitor during the search phase. The bears did not achieve above-chance recovery accuracy even in the presence of a competitor. In Experiment 3, the same two of four sites were continually baited and the bears were released simultaneously over a period of 20 days, with each baiting separated by 2 or 3 days. As a group, the bears' foraging accuracy with repeated baiting and longer intervals approached greater than chance accuracy. Results suggest some limitations on bears' use of spatial memory in captive environments, but reveal the potential for use of spatial memory over longer delays. PMID:22545764

  9. Neutralizer optimization

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J.; Mohajeri, Kayhan

    1991-01-01

    The preliminary results of a test program to optimize a neutralizer design for 30 cm xenon ion thrusters are discussed. The impact of neutralizer geometry, neutralizer axial location, and local magnetic fields on neutralizer performance is discussed. The effect of neutralizer performance on overall thruster performance is quantified, for thruster operation in the 0.5-3.2 kW power range. Additionally, these data are compared to data published for other north-south stationkeeping (NSSK) and primary propulsion xenon ion thruster neutralizers.

  10. The complete genome sequence of 'Candidatus Liberibacter americanus', associated with Citrus huanglongbing.

    PubMed

    Wulff, Nelson A; Zhang, Shujian; Setubal, João C; Almeida, Nalvo F; Martins, Elaine C; Harakava, Ricardo; Kumar, Dibyendu; Rangel, Luiz Thiberio; Foissac, Xavier; Bové, Joseph M; Gabriel, Dean W

    2014-02-01

    Liberibacter spp. form a Rhizobiaceae clade of phloem-limited pathogens of limited host range. Two obligately parasitic species have been sequenced: 'Candidatus Liberibacter asiaticus', which causes citrus huanglongbing (HLB) worldwide, and 'Ca. L. solanacearum', which causes potato "zebra chip" disease. A third (proposed) species, Liberibacter crescens, was isolated from mountain papaya, grown in axenic culture, and sequenced. In an effort to identify common host determinants, the complete genomic DNA sequence of a second HLB species, 'Ca. L. americanus' strain 'São Paulo' was determined. The circular genome of 1,195,201 bp had an average 31.12% GC content and 983 predicted protein encoding genes, 800 (81.4%) of which had a predicted function. There were 658 genes common to all sequenced Liberibacter spp. and only 8 genes common to 'Ca. L. americanus' and 'Ca. L. asiaticus' but not found in 'Ca. L. solanacearum'. Surprisingly, most of the lipopolysaccharide biosynthetic genes were missing from the 'Ca. L. americanus' genome, as well as OmpA and a key regulator of flagellin, all indicating a 'Ca. L. americanus' strategy of avoiding production of major pathogen-associated molecular patterns present in 'Ca. L. asiaticus' and 'Ca. L. solanacearum'. As with 'Ca. L. asiaticus', one of two 'Ca. L. americanus' prophages replicated as an excision plasmid and carried potential lysogenic conversion genes that appeared fragmentary or degenerated in 'Ca. L. solanacearum'.

  11. TNFα-induced neutral sphingomyelinase-2 modulates synaptic plasticity by controlling the membrane insertion of NMDA receptors

    PubMed Central

    Wheeler, David; Knapp, Edward; Bandaru, Veera V.R.; Wang, Yue; Knorr, David; Poirier, Christophe; Mattson, Mark P.; Geiger, Jonathan D.; Haughey, Norman J.

    2009-01-01

    The insertion and removal of N-methyl D-aspartate (NMDA) receptors from the synapse are critical events that modulate synaptic plasticity. While a great deal of progress has been made on understanding the mechanisms that modulate trafficking of NMDA receptors, we do not currently understand the molecular events required for the fusion of receptor containing vesicles with the plasma membrane. Here we show that sphingomyelin phosphodiesterase3 (also known as neutral sphingomyelinase-2; nSMase2) is critical for TNFα-induced trafficking of NMDA receptors and synaptic plasticity. TNFα initiated a rapid increase in ceramide that was associated with increased surface localization of NMDA receptor NR1 subunits and a specific clustering of NR1 phosphorylated on serines 896 and 897 into lipid rafts. Brief applications of TNFα increased the rate and amplitude of NMDA-evoked calcium bursts and enhanced excitatory postsynaptic currents (EPSCs). Pharmacological inhibition or genetic mutation of nSMase2 prevented TNFα-induced generation of ceramide, phosphorylation of NR1 subuints, clustering of NR1, enhancement of NMDA-evoked calcium flux and EPSCs. PMID:19476542

  12. Ebola virus-like particles produced in insect cells exhibit dendritic cell stimulating activity and induce neutralizing antibodies

    SciTech Connect

    Ye Ling; Lin Jianguo; Sun Yuliang; Bennouna, Soumaya; Lo, Michael; Wu Qingyang; Bu Zhigao; Pulendran, Bali; Compans, Richard W. . E-mail: compans@microbio.emory.edu; Yang Chinglai . E-mail: chyang@emory.edu

    2006-08-01

    Recombinant baculoviruses (rBV) expressing Ebola virus VP40 (rBV-VP40) or GP (rBV-GP) proteins were generated. Infection of Sf9 insect cells by rBV-VP40 led to assembly and budding of filamentous particles from the cell surface as shown by electron microscopy. Ebola virus-like particles (VLPs) were produced by coinfection of Sf9 cells with rBV-VP40 and rBV-GP, and incorporation of Ebola GP into VLPs was demonstrated by SDS-PAGE and Western blot analysis. Recombinant baculovirus infection of insect cells yielded high levels of VLPs, which were shown to stimulate cytokine secretion from human dendritic cells similar to VLPs produced in mammalian cells. The immunogenicity of Ebola VLPs produced in insect cells was evaluated by immunization of mice. Analysis of antibody responses showed that most of the GP-specific antibodies were of the IgG2a subtype, while no significant level of IgG1 subtype antibodies specific for GP was induced, indicating the induction of a Th1-biased immune response. Furthermore, sera from Ebola VLP immunized mice were able to block infection by Ebola GP pseudotyped HIV virus in a single round infection assay, indicating that a neutralizing antibody against the Ebola GP protein was induced. These results show that production of Ebola VLPs in insect cells using recombinant baculoviruses represents a promising approach for vaccine development against Ebola virus infection.

  13. Inhibition of neutral sphingomyelinase decreases elevated levels of inducible nitric oxide synthase and apoptotic cell death in ocular hypertensive rats

    SciTech Connect

    Aslan, Mutay; Basaranlar, Goksun; Unal, Mustafa; Ciftcioglu, Akif; Derin, Narin; Mutus, Bulent

    2014-11-01

    Endoplasmic reticulum (ER) stress and excessive nitric oxide production via induction of inducible nitric oxide synthase (NOS2) have been implicated in the pathogenesis of neuronal retinal cell death in ocular hypertension. Neutral sphingomyelinase (N-SMase)/ceramide pathway can regulate NOS2 expression, hence this study determined the role of selective neutral sphingomyelinase (N-SMase) inhibition on retinal NOS2 levels, ER stress, apoptosis and visual evoked potentials (VEPs) in a rat model of elevated intraocular pressure (EIOP). NOS2 expression and retinal protein nitration were significantly greater in EIOP and significantly decreased with N-SMase inhibition. A significant increase was observed in retinal ER stress markers pPERK, CHOP and GRP78 in EIOP, which were not significantly altered by N-SMase inhibition. Retinal TUNEL staining showed increased apoptosis in all EIOP groups; however N-SMase inhibition significantly decreased the percent of apoptotic cells in EIOP. Caspase-3, -8 and -9 activities were significantly increased in EIOP and returned to baseline levels following N-SMase inhibition. Latencies of all VEP components were significantly prolonged in EIOP and shortened following N-SMase inhibition. Data confirm the role of nitrative injury in EIOP and highlight the protective effect of N-SMase inhibition in EIOP via down-regulation of NOS2 levels and nitrative stress. - Highlights: • Inhibition of N-SMase decreases NOS2 levels in ocular hypertension. • Inhibition of N-SMase decreases protein nitration in ocular hypertension. • Inhibition of N-SMase decreases caspase activation in ocular hypertension. • Inhibition of N-SMase decreases apoptosis in ocular hypertension.

  14. Laser neutralization

    SciTech Connect

    Peterson, O.G.

    1986-06-17

    Laser photodetachment of the excess electron to neutralize relativistic ions offers many advantages over the more conventional collisional methods using gases or thin foils as the neutralization agents. Probably the two most important advantages of laser photodetachment are the generation of a compact and low divergence beam, and the production of intense neutral beams at very high efficiency (approximately 90%). The high intensities or high current densities of the neutral beam result from the fixed maximum divergence that can be added to the beam by photodetachment of the charge using laser intensity of fixed wavelength and incident angle. The high neutralization efficiency is possible because there is no theoretical maximum to the neutralization efficiency, although higher efficiencies require higher laser powers and, therefore, costs. Additional advantages include focusability of the laser light onto the ion beam to maximize its efficacy. There certainly is no residual gas left in the particle beam path as is typical with gas neutralizers. The photodetachment process leaves the neutral atoms in the ground state so there is no excited state fluorescence to interfere with the subsequent beam sensing. Finally, since the beams to be neutralized are very high powered, for a large range of neutralization efficiencies the neutral beam can be increased more by increasing the power to the laser neutralizer than by adding an equal amount of power to the primary accelerator. 26 figs.

  15. Activity of Ca2+-dependent neutral proteases in tissues of ground squirrel during hibernation and during self-warming after induced awakening.

    PubMed

    Nurmagomedova, P M; Abasova, M M; Emirbekov, E Z

    2011-09-01

    Cyclic changes in activity of Ca2+-dependent neutral protease occur during preparation for hibernation, with an increase in September and November and decrease in October and December. During hibernation proteolytic enzyme activity decreased, while during self-warming after induced awakening, the role of Ca2+-dependent processes in the tissues of ground squirrels increased according to the body temperature.

  16. A novel “correlated ion and neutral time of flight” method: Event-by-event detection of neutral and charged fragments in collision induced dissociation of mass selected ions

    SciTech Connect

    Teyssier, C.; Fillol, R.; Abdoul-Carime, H.; Farizon, B.; Farizon, M.

    2014-01-15

    A new tandem mass spectrometry (MS/MS) method based on time of flight measurements performed on an event-by-event detection technique is presented. This “correlated ion and neutral time of flight” method allows to explore Collision Induced Dissociation (CID) fragmentation processes by directly identifying not only all ions and neutral fragments produced but also their arrival time correlations within each single fragmentation event from a dissociating molecular ion. This constitutes a new step in the characterization of molecular ions. The method will be illustrated here for a prototypical case involving CID of protonated water clusters H{sup +}(H{sub 2}O){sub n=1–5} upon collisions with argon atoms.

  17. Comparative study on the ability of IgG and F(ab')2 antivenoms to neutralize lethal and myotoxic effects induced by Micrurus nigrocinctus (coral snake) venom.

    PubMed

    León, G; Stiles, B; Alape, A; Rojas, G; Gutiérrez, J M

    1999-08-01

    A comparative study was performed on the ability of IgG and F(ab')2 antivenoms to neutralize lethal and myotoxic activities of Micrurus nigrocinctus venom. Both antivenoms were adjusted to a similar neutralizing potency in experiments where venom and antivenoms were preincubated prior to injection. No significant differences were observed between IgG and F(ab')2 antivenoms concerning neutralization of lethal effect in rescue experiments, i.e., when antivenom was administered intravenously after envenomation. However, F(ab')2 antivenom was more effective in prolonging the time of death when subneutralizing doses were administered immediately after venom injection. Both products partially reversed the binding of M. nigrocinctus alpha-neurotoxins to acetylcholine receptor in vitro. The IgG and F(ab')2 antivenoms effectively neutralized venom-induced myotoxicity when administered intravenously immediately after envenomation, although neutralization was poor if antivenom injections were delayed. Intramuscular injection of venom promoted diffusion of antivenom antibodies throughout muscle tissue, and F(ab')2 diffused to a higher extent than IgG molecules. Thus, despite the observation that F(ab')2 antivenom was more effective than IgG antivenom in prolonging the time of death when subneutralizing doses were administered immediately after envenomation, no major differences were observed in antivenom neutralization of lethal and myotoxic effects or in their capacity to reverse neurotoxin binding to the acetylcholine receptor.

  18. Taxonomic recovery of the ant cricket Myrmecophilus albicinctus from M. americanus (Orthoptera, Myrmecophilidae).

    PubMed

    Komatsu, Takashi; Maruyama, Munetoshi

    2016-01-01

    Myrmecophilus americanus and Myrmecophilus albicinctus are typical myrmecophilous insects living inside ant nests. These species are ecologically important due to the obligate association with tramp ant species, including harmful invasive ant species. However, the taxonomy of these "white-banded ant crickets" is quite confused owing to a scarcity of useful external morphological characteristics. Recently, Myrmecophilus albicinctus was synonymized with Myrmecophilus americanus regardless of the apparent host use difference. To clarify taxonomical relationship between Myrmecophilus albicinctus and Myrmecophilus albicinctus, we reexamined morphological characteristics of both species mainly in the viewpoint of anatomy. Observation of genitalia parts, together with a few external body parts, revealed that Myrmecophilus albicinctus showed different tendency from them of Myrmecophilus americanus. Therefore, we recover Myrmecophilus albicinctus as a distinct species on the basis of the morphology. PMID:27408536

  19. Taxonomic recovery of the ant cricket Myrmecophilus albicinctus from M. americanus (Orthoptera, Myrmecophilidae)

    PubMed Central

    Komatsu, Takashi; Maruyama, Munetoshi

    2016-01-01

    Abstract Myrmecophilus americanus and Myrmecophilus albicinctus are typical myrmecophilous insects living inside ant nests. These species are ecologically important due to the obligate association with tramp ant species, including harmful invasive ant species. However, the taxonomy of these “white-banded ant crickets” is quite confused owing to a scarcity of useful external morphological characteristics. Recently, Myrmecophilus albicinctus was synonymized with Myrmecophilus americanus regardless of the apparent host use difference. To clarify taxonomical relationship between Myrmecophilus albicinctus and Myrmecophilus albicinctus, we reexamined morphological characteristics of both species mainly in the viewpoint of anatomy. Observation of genitalia parts, together with a few external body parts, revealed that Myrmecophilus albicinctus showed different tendency from them of Myrmecophilus americanus. Therefore, we recover Myrmecophilus albicinctus as a distinct species on the basis of the morphology. PMID:27408536

  20. Neutralization, by a monospecific Bothrops lanceolatus antivenom, of toxic activities induced by homologous and heterologous Bothírops snake venoms.

    PubMed

    Bogarín, G; Romero, M; Rojas, G; Lutsch, C; Casadamont, M; Lang, J; Otero, R; Gutiérrez, J M

    1999-03-01

    A monospecific Bothrops lanceolatus antivenom, currently used in Martinique, was tested for its efficacy in the neutralization of several toxic and enzymatic activities of the venoms of B. lanceolatus, B. atrox and B. asper. When tested by the i.p. route in mice, B. lanceolatus venom had an LD50 of 12.8 microg/g. In addition, it induced local tissue damage (hemorrhage, edema and myotoxicity) and showed indirect hemolytic activity, but was devoid of coagulant effect on human plasma in vitro and of defibrinating activity in mice. Antivenom was fully effective in the neutralization of lethal, hemorrhagic, edema-forming, myotoxic and indirect hemolytic effects of B. lanceolatus venom in assays involving preincubation of venom and antivenom. When tested against the venoms of B. asper and B. atrox, the antivenom completely neutralized the lethal, hemorrhagic, myotoxic and indirect hemolytic effects, and was partially effective in neutralizing edema-forming activity. In contrast, the antivenom was ineffective in the neutralization of in vitro coagulant and in vivo defibrinating effects induced by these two venoms. PMID:10080358

  1. Characterization and functional classification of American lobster (Homarus americanus) immune factor transcripts.

    PubMed

    Clark, K Fraser

    2014-11-01

    The American lobster (Homarus americanus) is the most important commercially exploited marine species in Canada. Very little is known about the H. americanus molecular humoral immune response or how to determine if a seemingly healthy lobster is infected with a pathogen. The goal of this work is to characterize several important H. americanus immune genes as well as highlight and classify hundreds of others into functional immune groups. The protein sequence of H. americanus acute phase serum amyloid protein A (SAA) was found to be similar to that of vertebrate SAA, and is likely a good clinical marker for immune activation in lobsters and some crustaceans. Additionally, only one gene, Trypsin 1b, was found to be differentially regulated during bacterial, microparasitic and viral challenges in lobster and is likely critical for the activation of the H. americanus immune response. Bioinformatic analysis was used to functionally annotate, 263 H. americanus immune genes and identify the few shared patterns of differential gene expression in lobsters in response to bacterial, parasitic and viral challenge. Many of the described immune genes are biomarker candidates which could be used as clinical indicators for lobster health and disease. Biomarkers can facilitate early detection of pathogens, or anthropomorphic stressors, so that mitigation strategies can be developed in order to prevent the devastating economic losses that have occurred in Southern New England, USA. This work is contributes to further our understanding of how the lobster immune system works and how it can be used to maintain the health and sustainability of the overall American lobster fishery.

  2. Neuropeptidergic Signaling in the American Lobster Homarus americanus: New Insights from High-Throughput Nucleotide Sequencing.

    PubMed

    Christie, Andrew E; Chi, Megan; Lameyer, Tess J; Pascual, Micah G; Shea, Devlin N; Stanhope, Meredith E; Schulz, David J; Dickinson, Patsy S

    2015-01-01

    Peptides are the largest and most diverse class of molecules used for neurochemical communication, playing key roles in the control of essentially all aspects of physiology and behavior. The American lobster, Homarus americanus, is a crustacean of commercial and biomedical importance; lobster growth and reproduction are under neuropeptidergic control, and portions of the lobster nervous system serve as models for understanding the general principles underlying rhythmic motor behavior (including peptidergic neuromodulation). While a number of neuropeptides have been identified from H. americanus, and the effects of some have been investigated at the cellular/systems levels, little is currently known about the molecular components of neuropeptidergic signaling in the lobster. Here, a H. americanus neural transcriptome was generated and mined for sequences encoding putative peptide precursors and receptors; 35 precursor- and 41 receptor-encoding transcripts were identified. We predicted 194 distinct neuropeptides from the deduced precursor proteins, including members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C, bursicon, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, FLRFamide, GSEFLamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin-related peptide families. While some of the predicted peptides are known H. americanus isoforms, most are novel identifications, more than doubling the extant lobster neuropeptidome. The deduced receptor proteins are the first descriptions of H. americanus neuropeptide receptors, and include ones for most of the peptide groups mentioned earlier, as well as those for ecdysis-triggering hormone, red pigment concentrating hormone

  3. Characterization and functional classification of American lobster (Homarus americanus) immune factor transcripts.

    PubMed

    Clark, K Fraser

    2014-11-01

    The American lobster (Homarus americanus) is the most important commercially exploited marine species in Canada. Very little is known about the H. americanus molecular humoral immune response or how to determine if a seemingly healthy lobster is infected with a pathogen. The goal of this work is to characterize several important H. americanus immune genes as well as highlight and classify hundreds of others into functional immune groups. The protein sequence of H. americanus acute phase serum amyloid protein A (SAA) was found to be similar to that of vertebrate SAA, and is likely a good clinical marker for immune activation in lobsters and some crustaceans. Additionally, only one gene, Trypsin 1b, was found to be differentially regulated during bacterial, microparasitic and viral challenges in lobster and is likely critical for the activation of the H. americanus immune response. Bioinformatic analysis was used to functionally annotate, 263 H. americanus immune genes and identify the few shared patterns of differential gene expression in lobsters in response to bacterial, parasitic and viral challenge. Many of the described immune genes are biomarker candidates which could be used as clinical indicators for lobster health and disease. Biomarkers can facilitate early detection of pathogens, or anthropomorphic stressors, so that mitigation strategies can be developed in order to prevent the devastating economic losses that have occurred in Southern New England, USA. This work is contributes to further our understanding of how the lobster immune system works and how it can be used to maintain the health and sustainability of the overall American lobster fishery. PMID:24981290

  4. Neuropeptidergic Signaling in the American Lobster Homarus americanus: New Insights from High-Throughput Nucleotide Sequencing.

    PubMed

    Christie, Andrew E; Chi, Megan; Lameyer, Tess J; Pascual, Micah G; Shea, Devlin N; Stanhope, Meredith E; Schulz, David J; Dickinson, Patsy S

    2015-01-01

    Peptides are the largest and most diverse class of molecules used for neurochemical communication, playing key roles in the control of essentially all aspects of physiology and behavior. The American lobster, Homarus americanus, is a crustacean of commercial and biomedical importance; lobster growth and reproduction are under neuropeptidergic control, and portions of the lobster nervous system serve as models for understanding the general principles underlying rhythmic motor behavior (including peptidergic neuromodulation). While a number of neuropeptides have been identified from H. americanus, and the effects of some have been investigated at the cellular/systems levels, little is currently known about the molecular components of neuropeptidergic signaling in the lobster. Here, a H. americanus neural transcriptome was generated and mined for sequences encoding putative peptide precursors and receptors; 35 precursor- and 41 receptor-encoding transcripts were identified. We predicted 194 distinct neuropeptides from the deduced precursor proteins, including members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C, bursicon, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, FLRFamide, GSEFLamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin-related peptide families. While some of the predicted peptides are known H. americanus isoforms, most are novel identifications, more than doubling the extant lobster neuropeptidome. The deduced receptor proteins are the first descriptions of H. americanus neuropeptide receptors, and include ones for most of the peptide groups mentioned earlier, as well as those for ecdysis-triggering hormone, red pigment concentrating hormone

  5. Neuropeptidergic Signaling in the American Lobster Homarus americanus: New Insights from High-Throughput Nucleotide Sequencing

    PubMed Central

    Christie, Andrew E.; Chi, Megan; Lameyer, Tess J.; Pascual, Micah G.; Shea, Devlin N.; Stanhope, Meredith E.; Schulz, David J.; Dickinson, Patsy S.

    2015-01-01

    Peptides are the largest and most diverse class of molecules used for neurochemical communication, playing key roles in the control of essentially all aspects of physiology and behavior. The American lobster, Homarus americanus, is a crustacean of commercial and biomedical importance; lobster growth and reproduction are under neuropeptidergic control, and portions of the lobster nervous system serve as models for understanding the general principles underlying rhythmic motor behavior (including peptidergic neuromodulation). While a number of neuropeptides have been identified from H. americanus, and the effects of some have been investigated at the cellular/systems levels, little is currently known about the molecular components of neuropeptidergic signaling in the lobster. Here, a H. americanus neural transcriptome was generated and mined for sequences encoding putative peptide precursors and receptors; 35 precursor- and 41 receptor-encoding transcripts were identified. We predicted 194 distinct neuropeptides from the deduced precursor proteins, including members of the adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin C, bursicon, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone (CHH), CHH precursor-related peptide, diuretic hormone 31, diuretic hormone 44, eclosion hormone, FLRFamide, GSEFLamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, proctolin, pyrokinin, SIFamide, sulfakinin and tachykinin-related peptide families. While some of the predicted peptides are known H. americanus isoforms, most are novel identifications, more than doubling the extant lobster neuropeptidome. The deduced receptor proteins are the first descriptions of H. americanus neuropeptide receptors, and include ones for most of the peptide groups mentioned earlier, as well as those for ecdysis-triggering hormone, red pigment concentrating hormone

  6. CGP 44532, a GABAB receptor agonist, is hedonically neutral and reduces cocaine-induced enhancement of reward.

    PubMed

    Dobrovitsky, V; Pimentel, P; Duarte, A; Froestl, W; Stellar, J R; Trzcińska, M

    2002-04-01

    Drugs that alter the function of gamma-aminobutyric acid (GABA) neurotransmission seem to reduce cocaine reinforcement, and as such may be useful in pharmacologically treating cocaine addiction. In the present experiment, the anti-cocaine effects of CGP 44532, a phosphinic acid analogue of GABA, and a highly selective GABA(B) receptor agonist were examined in male Sprague-Dawley rats using brain stimulation reward (BSR) paradigm. In this method, the relationship between the rate of bar pressing and the frequency of stimulation pulses was analyzed in two measures: the maximum rate of responding (MAX) and the frequency necessary to sustain half maximal rate of responding known as the locus of rise (LOR). CGP 44532 was found to be hedonically neutral without producing any measurable effects on performance (MAX). It also dose-dependently reduced cocaine-induced BSR enhancement, in the order of 15-31%, as shown by progressive shifts in LOR towards baseline. Thus, in theory, administration of CGP 44532 might reduce cocaine's hedonic effects, while also maintaining patient compliance. Whether this agent would also be effective at curbing craving, a long-term consequence of drug abuse, remains to be determined.

  7. Procalcitonin neutralizes bacterial LPS and reduces LPS-induced cytokine release in human peripheral blood mononuclear cells

    PubMed Central

    2012-01-01

    Background Procalcitonin (PCT) is a polypeptide with several cationic aminoacids in its chemical structure and it is a well known marker of sepsis. It is now emerging that PCT might exhibit some anti-inflammatory effects. The present study, based on the evaluation of the in vitro interaction between PCT and bacterial lipopolisaccharide (LPS), reports new data supporting the interesting and potentially useful anti-inflammatory activity of PCT. Results PCT significantly decreased (p < 0.05) the limulus amoebocyte lysate (LAL) assay reactivity of LPS from both Salmonella typhimurium (rough chemotype) and Escherichia coli (smooth chemotype). Subsequently, the in vitro effects of PCT on LPS-induced cytokine release were studied in human peripheral blood mononuclear cells (PBMC). When LPS was pre-incubated for 30 minutes with different concentrations of PCT, the release of interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) by PBMC decreased in a concentration-dependent manner after 24 hours for IL-10 and 4 hours for TNFα. The release of monocyte chemotactic protein-1 (MCP-1) exhibited a drastic reduction at 4 hours for all the PCT concentrations assessed, whereas such decrease was concentration-dependent after 24 hours. Conclusions This study provides the first evidence of the capability of PCT to directly neutralize bacterial LPS, thus leading to a reduction of its major inflammatory mediators. PMID:22568957

  8. The empirical dependence of radiation-induced charge neutralization on negative bias in dosimeters based on the metal-oxide-semiconductor field-effect transistor

    SciTech Connect

    Benson, Chris; Albadri, Abdulrahman; Joyce, Malcolm J.; Price, Robert A.

    2006-08-15

    The dependence of radiation-induced charge neutralization (RICN) has been studied in metal-oxide-semiconductor field-effect transistor (MOSFET) dosimeters. These devices were first exposed to x rays under positive bias and then to further dose increments at a selection of reverse bias levels. A nonlinear empirical trend has been established that is consistent with that identified in the data obtained in this work. Estimates for the reverse bias level corresponding to the maximum rate of RICN have been extracted from the data. These optimum bias levels appear to be independent of the level of initial absorbed dose under positive bias. The established models for threshold voltage change have been considered and indicate a related nonlinear trend for neutralization cross section {sigma}{sub N} as a function of oxide field. These data are discussed in the context of dose measurement with MOSFETs and within the framework of statistical mechanics associated with neutral traps and their field dependence.

  9. The Inhibitory Effects of Anti-Oxidants on Ultraviolet-Induced Up-Regulation of the Wrinkling-Inducing Enzyme Neutral Endopeptidase in Human Fibroblasts

    PubMed Central

    Nakajima, Hiroaki; Terazawa, Shuko; Niwano, Takao; Yamamoto, Yorihiro; Imokawa, Genji

    2016-01-01

    We recently reported that the over-expression of skin fibroblast-derived neutral endopeptidase (NEP) plays a pivotal role in impairing the three-dimensional architecture of dermal elastic fibers during the biological mechanism of ultraviolet (UV)-induced skin wrinkling. In that process, a UVB-associated epithelial-mesenchymal cytokine interaction as well as a direct UVA-induced cellular stimulation are associated with the up-regulation of NEP in human fibroblasts. In this study, we characterized the mode of action of ubiquinol10 which may abrogate the up-regulation of NEP by dermal fibroblasts, resulting in a reported in vivo anti-wrinkling action, and compared that with 3 other anti-oxidants, astaxanthin (AX), riboflavin (RF) and flavin mononucleotide (FMN). Post-irradiation treatment with all 4 of those anti-oxidants elicited an interrupting effect on the UVB-associated epithelial-mesenchymal cytokine interaction leading to the up-regulation of NEP in human fibroblasts but with different modes of action. While AX mainly served as an inhibitor of the secretion of wrinkle-inducing cytokines, such as interleukin-1α (IL-1α) and granulocyte macrophage colony stimulatory factor (GM-CSF) in UVB-exposed epidermal keratinocytes, ubiquinol10, RF and FMN predominantly interrupted the IL-1α and GM-CSF-stimulated expression of NEP in dermal fibroblasts. On the other hand, as for the UVA-associated mechanism, similar to the abrogating effects reported for AX and FMN, ubiquinol10 but not RF had the potential to abrogate the increased expression of NEP and matrix-metalloproteinase-1 in UVA-exposed human fibroblasts. Our findings strongly support the in vivo anti-wrinkling effects of ubiquinol10 and AX on human and animal skin and provide convincing proof of the UV-induced wrinkling mechanism that essentially focuses on the over-expression of NEP by dermal fibroblasts as an intrinsic causative factor. PMID:27648570

  10. The Inhibitory Effects of Anti-Oxidants on Ultraviolet-Induced Up-Regulation of the Wrinkling-Inducing Enzyme Neutral Endopeptidase in Human Fibroblasts.

    PubMed

    Nakajima, Hiroaki; Terazawa, Shuko; Niwano, Takao; Yamamoto, Yorihiro; Imokawa, Genji

    2016-01-01

    We recently reported that the over-expression of skin fibroblast-derived neutral endopeptidase (NEP) plays a pivotal role in impairing the three-dimensional architecture of dermal elastic fibers during the biological mechanism of ultraviolet (UV)-induced skin wrinkling. In that process, a UVB-associated epithelial-mesenchymal cytokine interaction as well as a direct UVA-induced cellular stimulation are associated with the up-regulation of NEP in human fibroblasts. In this study, we characterized the mode of action of ubiquinol10 which may abrogate the up-regulation of NEP by dermal fibroblasts, resulting in a reported in vivo anti-wrinkling action, and compared that with 3 other anti-oxidants, astaxanthin (AX), riboflavin (RF) and flavin mononucleotide (FMN). Post-irradiation treatment with all 4 of those anti-oxidants elicited an interrupting effect on the UVB-associated epithelial-mesenchymal cytokine interaction leading to the up-regulation of NEP in human fibroblasts but with different modes of action. While AX mainly served as an inhibitor of the secretion of wrinkle-inducing cytokines, such as interleukin-1α (IL-1α) and granulocyte macrophage colony stimulatory factor (GM-CSF) in UVB-exposed epidermal keratinocytes, ubiquinol10, RF and FMN predominantly interrupted the IL-1α and GM-CSF-stimulated expression of NEP in dermal fibroblasts. On the other hand, as for the UVA-associated mechanism, similar to the abrogating effects reported for AX and FMN, ubiquinol10 but not RF had the potential to abrogate the increased expression of NEP and matrix-metalloproteinase-1 in UVA-exposed human fibroblasts. Our findings strongly support the in vivo anti-wrinkling effects of ubiquinol10 and AX on human and animal skin and provide convincing proof of the UV-induced wrinkling mechanism that essentially focuses on the over-expression of NEP by dermal fibroblasts as an intrinsic causative factor. PMID:27648570

  11. Oocyte recovery and maturation in the American black bear (Ursus americanus): a model for endangered ursids.

    PubMed

    Johnston, L A; Donoghue, A M; Igo, W; Simmons, L G; Wildt, D E; Rieffenberger, J

    1994-05-15

    A study was conducted to determine if meiotic maturation could be induced in ovarian oocytes of the American black bear (Ursus americanus), a model for gamete "rescue" techniques for endangered ursids. Ovaries obtained from 48 black bears yielded 2,403 oocytes (51.1 +/- 4.9/female), of which 777 (32.3%) were morphologically classified as excellent quality. More total oocytes were recovered from donors that were anestrous compared to luteal/pregnant (P < 0.05) at the time of ovarian excision. Delaying the recovery of oocytes from antral follicles within excised ovaries from 12-24 hr to 25-36 hr had no effect (P > 0.05) on the overall number of high quality oocytes recovered or subsequent maturational ability. The highest incidence of metaphase II was reached between 48 and 60 hr of in vitro incubation. Donor status (anestrous vs. luteal/pregnant) had no influence on the oocyte maturation rate by 24 or 48 hr, but by 60 hr, more (P < 0.05) oocytes recovered from anestrous females (43.9%) had achieved metaphase II compared to luteal/pregnant counterparts (23.1%). In preliminary trials involving endangered ursids, 54 ovarian oocytes were recovered from three aged sun bears (Helarctos malayanus), of which 72.2% were excellent quality and 15.4% matured in vitro to metaphase II. Similarly, 119 antral oocytes were recovered from two aged sloth bears (Melursus ursinus), of which 41.2% were excellent and 17.5% matured in vitro.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8207381

  12. Hepatitis C Virus Hypervariable Region 1 Variants Presented on Hepatitis B Virus Capsid-Like Particles Induce Cross-Neutralizing Antibodies

    PubMed Central

    Bankwitz, Dorothea; Osburn, William; Viazov, Sergei; Brovko, Olena; Zekri, Abdel-Rahman; Khudyakov, Yury; Nassal, Michael; Pumpens, Paul; Pietschmann, Thomas; Timm, Jörg; Roggendorf, Michael; Walker, Andreas

    2014-01-01

    Hepatitis C virus (HCV) infection is still a serious global health burden. Despite improved therapeutic options, a preventative vaccine would be desirable especially in undeveloped countries. Traditionally, highly conserved epitopes are targets for antibody-based prophylactic vaccines. In HCV-infected patients, however, neutralizing antibodies are primarily directed against hypervariable region I (HVRI) in the envelope protein E2. HVRI is the most variable region of HCV, and this heterogeneity contributes to viral persistence and has thus far prevented the development of an effective HVRI-based vaccine. The primary goal of an antibody-based HCV vaccine should therefore be the induction of cross-reactive HVRI antibodies. In this study we approached this problem by presenting selected cross-reactive HVRI variants in a highly symmetric repeated array on capsid-like particles (CLPs). SplitCore CLPs, a novel particulate antigen presentation system derived from the HBV core protein, were used to deliberately manipulate the orientation of HVRI and therefore enable the presentation of conserved parts of HVRI. These HVRI-CLPs induced high titers of cross-reactive antibodies, including neutralizing antibodies. The combination of only four HVRI CLPs was sufficient to induce antibodies cross-reactive with 81 of 326 (24.8%) naturally occurring HVRI peptides. Most importantly, HVRI CLPs with AS03 as an adjuvant induced antibodies with a 10-fold increase in neutralizing capability. These antibodies were able to neutralize infectious HCVcc isolates and 4 of 19 (21%) patient-derived HCVpp isolates. Taken together, these results demonstrate that the induction of at least partially cross-neutralizing antibodies is possible. This approach might be useful for the development of a prophylactic HCV vaccine and should also be adaptable to other highly variable viruses. PMID:25014219

  13. SARCOCYSTIS URSUSI, N. SP (APICOMPLEXA; SARCOCYSTIDAE) FROM THE BLACK BEAR (URSUS AMERICANUS)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection with Sarcocystis species is common in hervibores but is rare in bears. Histological sections of 374 black bears (Ursus americanus) from Pennsylvania were examined for sarcocysts. A total of 3 sarcocysts were found in 3 bears, 1 sarcocyst per section. Sarcocysts from 2 bears were considered...

  14. Potential Vertical Transmission of Winter Ticks (Dermacentor albipictus) from Moose (Alces americanus) Dams to Neonates.

    PubMed

    Severud, William J; DelGiudice, Glenn D

    2016-01-01

    North American moose (Alces americanus) frequently become infested with winter ticks (Dermacentor albipictus). During capture of neonatal moose in northeastern Minnesota, US, in May-June 2013 and 2014, we recovered adult ticks from neonates, presumably vertically transferred from dams, heretofore, not documented. Infestations on neonates may have population-level implications.

  15. Stable Carbon and Oxygen Isotope Ratios of Otoliths Differentiate Winter Flounder (Pseudopleuonectes americanus) Habitats

    EPA Science Inventory

    Stable carbon (13C) and oxygen (18O) isotope ratios were measured in otoliths of juvenile winter flounder (Pseudopleuronectes americanus) collected from 18 nursery areas along the coast of Rhode Island, USA. Samples were obtained during June and July of 2002 from locations tha...

  16. Purified envelope glycoproteins from human immunodeficiency virus type 1 variants induce individual, type-specific neutralizing antibodies.

    PubMed Central

    Nara, P L; Robey, W G; Pyle, S W; Hatch, W C; Dunlop, N M; Bess, J W; Kelliher, J C; Arthur, L O; Fischinger, P J

    1988-01-01

    Repeated immunizations of goats, horses, or chimpanzees with envelope glycoprotein gp120 isolated from human immunodeficiency virus type 1 (HIV-1) resulted in type-specific neutralizing-antibody responses, which began to decay approximately 20 days following the administration of antigen. This was true repeatedly for serum samples from animals hyperimmunized with gp120s from either the HTLV-IIIB (IIIB) or the envelope-divergent HTLV-IIIRF (RF) HIV-1 isolates. Animals previously immunized with the IIIB gp120 were then inoculated with purified RF gp120. The first response in these animals was an anamnestic resurgence of neutralizing antibody to IIIB without detectable neutralizing antibody for RF. However, with later RF gp120 boosts, the IIIB neutralizing-antibody titers fell and an RF type-specific neutralizing-antibody response developed. When assessed with other HIV-1 variants, no group-specific neutralizing antibody was seen in any of the vaccination protocols evaluated. These results will pose real obstacles in the development of an effective vaccine for HIV. PMID:3392769

  17. Quetiapine Inhibits Microglial Activation by Neutralizing Abnormal STIM1-Mediated Intercellular Calcium Homeostasis and Promotes Myelin Repair in a Cuprizone-Induced Mouse Model of Demyelination

    PubMed Central

    Wang, Hanzhi; Liu, Shubao; Tian, Yanping; Wu, Xiyan; He, Yangtao; Li, Chengren; Namaka, Michael; Kong, Jiming; Li, Hongli; Xiao, Lan

    2015-01-01

    Microglial activation has been considered as a crucial process in the pathogenesis of neuroinflammation and psychiatric disorders. Several antipsychotic drugs (APDs) have been shown to display inhibitory effects on microglial activation in vitro, possibly through the suppression of elevated intracellular calcium (Ca2+) concentration. However, the exact underlying mechanisms still remain elusive. In this study, we aimed to investigate the inhibitory effects of quetiapine (Que), an atypical APD, on microglial activation. We utilized a chronic cuprizone (CPZ)-induced demyelination mouse model to determine the direct effect of Que on microglial activation. Our results showed that treatment with Que significantly reduced recruitment and activation of microglia/macrophage in the lesion of corpus callosum and promoted remyelination after CPZ withdrawal. Our in vitro studies also confirmed the direct effect of Que on lipopolysaccharide (LPS)-induced activation of microglial N9 cells, whereby Que significantly inhibited the release of nitric oxide (NO) and tumor necrosis factor α (TNF-α). Moreover, we demonstrated that pretreatment with Que, neutralized the up-regulation of STIM1 induced by LPS and declined both LPS and thapsigargin (Tg)-induced store-operated Ca2+ entry (SOCE). Finally, we found that pretreatment with Que significantly reduced the translocation of nuclear factor kappa B (NF-κB) p65 subunit from cytoplasm to nuclei in LPS-activated primary microglial cells. Overall, our data suggested that Que may inhibit microglial activation by neutralization of the LPS-induced abnormal STIM1-mediated intercellular calcium homeostasis. PMID:26732345

  18. Simulations of the Neutral-beam-induced Rotation, Radial Electric Field, and Flow Shearing Rate in Next-step Burning Plasmas

    SciTech Connect

    R.V. Budny

    2002-08-13

    Toroidal rotation of plasmas in present tokamaks is beneficial for increasing the stability to wall-induced MHD and appears to reduce the anomalous transport associated with micro-turbulence. This paper calculates the toroidal rotation expected from neutral-beam injection in the proposed FIRE and ITER-FEAT tokamak reactors. Self-consistent burning plasmas for these tokamaks have been constructed using the TRANSP plasma analysis code. Neutral-beam injection has been proposed for FIRE and ITER-FEAT. The neutral-beam-induced torques are computed, and assumptions for the anomalous transport of toroidal angular momentum are used to calculate the toroidal rotation profiles. The central Mach numbers are about 3-8%. The ratio of the rotation speed to the Alfvin speed is less than 1%. Assuming neoclassical poloidal rotation and force balance, the radial electric field and flow shearing rate are calculated. Peak shearing rates near the outboard edge are in the 10-100 krad/s range.

  19. Neutral and acidic products derived from hydroxyl radical-induced oxidation of arabinotriose assessed by electrospray ionisation mass spectrometry.

    PubMed

    Moreira, Ana S P; da Costa, Elisabete V; Evtuguin, Dmitry V; Coimbra, Manuel A; Nunes, Fernando M; Domingues, M Rosário M

    2014-04-01

    The oxidation of α-(1 → 5)-L-arabinotriose (Ara3), an oligosaccharide structurally related to side chains of coffee arabinogalactans, was studied in reaction with hydroxyl radicals generated under conditions of Fenton reaction (Fe(2+)/H2O2). The acidic and neutral oxidation products were separated by ligand exchange/size-exclusion chromatography, subsequently identified by electrospray ionisation mass spectrometry (ESI-MS) and structurally characterised by tandem MS (ESI-MS/MS). In acidic fraction were identified several oxidation products containing an acidic residue at the corresponding reducing end of Ara3, namely arabinonic acid, and erythronic, glyceric and glycolic acids formed by oxidative scission of the furanose ring. In neutral fractions were identified derivatives containing keto, hydroxy and hydroperoxy moieties, as well as derivatives resulting from the ring scission at the reducing end of Ara3. In both acidic and neutral fractions, beyond the trisaccharide derivatives, the corresponding di- and monosaccharide derivatives were identified indicating the occurrence of oxidative depolymerisation. The structural characterisation of these oxidation products by ESI-MS/MS allowed the differentiation of isobaric and isomeric species of acidic and neutral character. The species identified in this study may help in detection of roasting products associated with the free radical-mediated oxidation of coffee arabinogalactans.

  20. Robust In Vitro and In Vivo Neutralization against Multiple High-Risk HPV Types Induced by a Thermostable Thioredoxin-L2 Vaccine.

    PubMed

    Seitz, Hanna; Ribeiro-Müller, Lis; Canali, Elena; Bolchi, Angelo; Tommasino, Massimo; Ottonello, Simone; Müller, Martin

    2015-10-01

    Current prophylactic virus-like particle (VLP) human papillomavirus (HPV) vaccines are based on the L1 major capsid protein and provide robust but virus type-restricted protection. Moreover, VLP vaccines have a high production cost, require cold-chain storage, and are thus not readily implementable in developing countries, which endure 85% of the cervical cancer-related death burden worldwide. In contrast with L1, immunization with minor capsid protein L2 elicits broad cross-neutralization, and we previously showed that insertion of a peptide spanning amino acids 20-38 of L2 into bacterial thioredoxin (Trx) greatly enhances its immunogenicity. Building on this finding, we use, here, four different neutralization assays to demonstrate that low doses of a trivalent Trx-L2 vaccine, incorporating L2(20-38) epitopes from HPV16, HPV31 and HPV51, and formulated in a human-compatible adjuvant, induce broadly protective responses. Specifically, we show that this vaccine, which uses a far-divergent archaebacterial thioredoxin as scaffold and is amenable to an easy one-step thermal purification, induces robust cross-neutralization against 12 of the 13 known oncogenic HPV types. Immune performance measured with two different in vitro neutralization assays was corroborated by the results of mouse cervico-vaginal challenge and passive transfer experiments indicating robust cross-protection also in vivo. Altogether, our results attest to the potential of Trx-L2 as a thermostable second-generation HPV vaccine particularly well suited for low-resource countries.

  1. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus

    PubMed Central

    Rey-Burusco, M. Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R.; Roe, Andrew J.; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W.; Córsico, Betina; Smith, Brian O.

    2015-01-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein–ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male. PMID:26318523

  2. Diversity in the structures and ligand-binding sites of nematode fatty acid and retinol-binding proteins revealed by Na-FAR-1 from Necator americanus.

    PubMed

    Rey-Burusco, M Florencia; Ibáñez-Shimabukuro, Marina; Gabrielsen, Mads; Franchini, Gisela R; Roe, Andrew J; Griffiths, Kate; Zhan, Bin; Cooper, Alan; Kennedy, Malcolm W; Córsico, Betina; Smith, Brian O

    2015-11-01

    Fatty acid and retinol-binding proteins (FARs) comprise a family of unusual α-helix rich lipid-binding proteins found exclusively in nematodes. They are secreted into host tissues by parasites of plants, animals and humans. The structure of a FAR protein from the free-living nematode Caenorhabditis elegans is available, but this protein [C. elegans FAR-7 (Ce-FAR-7)] is from a subfamily of FARs that does not appear to be important at the host/parasite interface. We have therefore examined [Necator americanus FAR-1 (Na-FAR-1)] from the blood-feeding intestinal parasite of humans, N. americanus. The 3D structure of Na-FAR-1 in its ligand-free and ligand-bound forms, determined by NMR (nuclear magnetic resonance) spectroscopy and X-ray crystallography respectively, reveals an α-helical fold similar to Ce-FAR-7, but Na-FAR-1 possesses a larger and more complex internal ligand-binding cavity and an additional C-terminal α-helix. Titration of apo-Na-FAR-1 with oleic acid, analysed by NMR chemical shift perturbation, reveals that at least four distinct protein-ligand complexes can be formed. Na-FAR-1 and possibly other FARs may have a wider repertoire for hydrophobic ligand binding, as confirmed in the present study by our finding that a range of neutral and polar lipids co-purify with the bacterially expressed recombinant protein. Finally, we show by immunohistochemistry that Na-FAR-1 is present in adult worms with a tissue distribution indicative of possible roles in nutrient acquisition by the parasite and in reproduction in the male.

  3. Microlichus americanus acariasis in saffron finches (Sicalis flaveola) with dermatitis and feather loss.

    PubMed

    Rettenmund, Christy L; Ossiboff, Robert J; McAloose, Denise; Knee, Wayne; Wade, Susan E; Paré, Jean A

    2015-05-01

    Over a 5-year period, 13 saffron finches (Sicalis flaveola) housed in mixed aviaries at the Bronx Zoo (Bronx, New York) were examined with feather loss and dermatitis, primarily affecting the nape, neck, and dorsum. Feather loss, hyperkeratosis, epidermal hyperplasia, and mixed granulocytic and mononuclear inflammation were identified in biopsies from live birds and tissue sections from postmortem specimens. In 10 of 13 cases, sections of arthropod parasites were seen histologically within feather follicles and along the surface of affected skin. Based on morphological characteristics, mites recovered from samples of formalin-fixed skin in 4 birds were identified as Microlichus americanus, an epidermoptid mite infrequently reported from wild birds and hippoboscid flies. Gross and histological lesions strongly implicate M. americanus as the cause of dermatitis affecting practically all saffron finches in the collection.

  4. External morphology of the cycliophoran dwarf male: a comparative study of Symbion pandora and S. americanus

    NASA Astrophysics Data System (ADS)

    Neves, Ricardo Cardoso; da Cunha, Marina Ribeiro; Funch, Peter; Wanninger, Andreas; Kristensen, Reinhardt Møbjerg

    2010-09-01

    Cycliophora is a recently described phylum to which only two species have been assigned so far, Symbion pandora and S. americanus. The cycliophoran life cycle is complex and alternates between asexual and sexual stages. Although not recognized as an entirely independent free-swimming stage when the phylum was first described, the dwarf male has a remarkably complex bodyplan albeit its very small size (approx. 30-40 μm in length). Aiming to increase the knowledge on the gross morphology of the cycliophoran dwarf male, specimens from S. pandora and S. americanus were analyzed by scanning electron microscopy. In both species, anterior and ventral ciliated fields, as well as paired lateral sensorial organs, were identified, thus confirming previous observations. However, new details are described herein such as the penial pouch that encloses the penis. We compare our findings on both Symbion species with the data currently available on other metazoan dwarf males.

  5. A microchannel confocal examination of arsenic speciation and distribution in Bufo americanus

    NASA Astrophysics Data System (ADS)

    Nearing, Michelle M.; Koch, Iris; Gordon, Robert A.; Reimer, Kenneth J.

    2016-05-01

    We have used confocal methods to examine the distribution and speciation of arsenic within amphibian tissue (Bufo americanus) from a contaminated mine site. The use of new microchannel technology permits a confocal, and energy-independent, examination of a given voxel within the amphibian tissue without the need for sectioning. We observe differences in arsenic concentration and speciation depending on tissue type, with the Eberth- Katschenko layer in particular containing Mn, Fe, Cu and Zn in addition to Ca and pentavalent arsenic.

  6. Sequence data mining in search of hookworm (Necator americanus) microRNAs.

    PubMed

    Kulkarni, Abhijeet P; Mittal, Smriti P K

    2016-09-30

    The new world hookworm, Necator americanus is a soil-transmitted nematode responsible for Necatoriasis (a type of helminthiasis) in hosts such as humans, dogs, and cats. N. americanus genome and transcriptome has been sequenced and a draft assembly analysis has been published highlighting protein coding genes and possible drug target proteins. Hookworm microRNA identification, annotations and their public release is yet to be attempted. The same is evident from lack of hookworm miRNA information in related popular public nucleotide sequence repositories such as miRBase, GenBank, WormBase etc. Therefore, in the present study we addressed these issues using EST and assembled transcript sequence information of hookworm. Using computational approaches, we identified three miRNAs precursor sequences and their mature forms. We also identified their potential targets from hookworm ESTs and transcripts, and from human transcriptome. Overall, the results indicate presence of nematode specific miRNA homologs in N. americanus and shades light on their putative targets in worm itself and the human host. PMID:27259664

  7. Sequence data mining in search of hookworm (Necator americanus) microRNAs.

    PubMed

    Kulkarni, Abhijeet P; Mittal, Smriti P K

    2016-09-30

    The new world hookworm, Necator americanus is a soil-transmitted nematode responsible for Necatoriasis (a type of helminthiasis) in hosts such as humans, dogs, and cats. N. americanus genome and transcriptome has been sequenced and a draft assembly analysis has been published highlighting protein coding genes and possible drug target proteins. Hookworm microRNA identification, annotations and their public release is yet to be attempted. The same is evident from lack of hookworm miRNA information in related popular public nucleotide sequence repositories such as miRBase, GenBank, WormBase etc. Therefore, in the present study we addressed these issues using EST and assembled transcript sequence information of hookworm. Using computational approaches, we identified three miRNAs precursor sequences and their mature forms. We also identified their potential targets from hookworm ESTs and transcripts, and from human transcriptome. Overall, the results indicate presence of nematode specific miRNA homologs in N. americanus and shades light on their putative targets in worm itself and the human host.

  8. A novel replication-competent vaccinia vector MVTT is superior to MVA for inducing high levels of neutralizing antibody via mucosal vaccination.

    PubMed

    Huang, Xiaoxing; Lu, Bin; Yu, Wenbo; Fang, Qing; Liu, Li; Zhuang, Ke; Shen, Tingting; Wang, Haibo; Tian, Po; Zhang, Linqi; Chen, Zhiwei

    2009-01-01

    Mucosal vaccination offers great advantage for inducing protective immune response to prevent viral transmission and dissemination. Here, we report our findings of a head-to-head comparison of two viral vectors modified vaccinia Ankara (MVA) and a novel replication-competent modified vaccinia Tian Tan (MVTT) for inducing neutralizing antibodies (Nabs) via intramuscular and mucosal vaccinations in mice. MVTT is an attenuated variant of the wild-type VTT, which was historically used as a smallpox vaccine for millions of Chinese people. The spike glycoprotein (S) of SARS-CoV was used as the test antigen after the S gene was constructed in the identical genomic location of two vectors to generate vaccine candidates MVTT-S and MVA-S. Using identical doses, MVTT-S induced lower levels ( approximately 2-3-fold) of anti- SARS-CoV neutralizing antibodies (Nabs) than MVA-S through intramuscular inoculation. MVTT-S, however, was capable of inducing consistently 20-to-100-fold higher levels of Nabs than MVA-S when inoculated via either intranasal or intraoral routes. These levels of MVTT-S-induced Nab responses were substantially (approximately 10-fold) higher than that induced via the intramuscular route in the same experiments. Moreover, pre-exposure to the wild-type VTT via intranasal or intraoral route impaired the Nab response via the same routes of MVTT-S vaccination probably due to the pre-existing anti-VTT Nab response. The efficacy of intranasal or intraoral vaccination, however, was still 20-to-50-fold better than intramuscular inoculation despite the subcutaneous pre-exposure to wild-type VTT. Our data have implications for people who maintain low levels of anti-VTT Nabs after historical smallpox vaccination. MVTT is therefore an attractive live viral vector for mucosal vaccination.

  9. A multi-subunit Chlamydia vaccine inducing neutralizing antibodies and strong IFN-γ+ CMI responses protects against a genital infection in minipigs

    PubMed Central

    Bøje, Sarah; Olsen, Anja Weinreich; Erneholm, Karin; Agerholm, Jørgen Steen; Jungersen, Gregers; Andersen, Peter; Follmann, Frank

    2016-01-01

    Chlamydia is the most widespread sexually transmitted bacterial disease and a prophylactic vaccine is highly needed. Ideally, this vaccine is required to induce a combined response of Th1 cell-mediated immune (CMI) response in concert with neutralizing antibodies. Using a novel Göttingen minipig animal model, we evaluated the immunogenicity and efficacy of a multi-subunit vaccine formulated in the strong Th1-inducing adjuvant CAF01. We evaluated a mixture of two fusion proteins (Hirep1 and CTH93) designed to promote either neutralizing antibodies or cell-mediated immunity, respectively. Hirep1 is a novel immunogen based on the variant domain (VD) 4 region from major outer membrane protein (MOMP) serovar (Sv) D, SvE and SvF, and CTH93 is a fusion molecule of three antigens (CT043, CT414 and MOMP). Pigs were immunized twice intramuscularly with either Hirep1+CTH93/CAF01, UV-inactivated Chlamydia trachomatis SvD bacteria (UV-SvD/CAF01) or CAF01. The Hirep1+CTH93/CAF01 vaccine induced a strong CMI response against the vaccine antigens and high titers of antibodies, particularly against the VD4 region of MOMP. Sera from Hirep1+CTH93/CAF01 immunized pigs neutralized C. trachomatis SvD and SvF infectivity in vitro. Both Hirep1+CTH93/CAF01 and UV-SvD/CAF01 vaccination protected pigs against a vaginal C. trachomatis SvD infection. In conclusion, the Hirep1+CTH93/CAF01 vaccine proved highly immunogenic and equally protective as UV-SvD/CAF01 showing promise for the development of a subunit vaccine against Chlamydia. PMID:26268662

  10. A highly conserved epitope-vaccine candidate against varicella-zoster virus induces neutralizing antibodies in mice.

    PubMed

    Zhu, Rui; Liu, Jian; Chen, Chunye; Ye, Xiangzhong; Xu, Longfa; Wang, Wei; Zhao, Qinjian; Zhu, Hua; Cheng, Tong; Xia, Ningshao

    2016-03-18

    Varicella-zoster virus (VZV) is a highly infectious agent of varicella and herpes zoster (HZ). Vaccination is by far the most effective way to prevent these diseases. More safe, stable and efficient vaccines, such as epitope-based vaccines, now have been increasingly investigated by many researchers. However, only a few VZV neutralizing epitopes have been identified to date. We have previously identified a linear epitope between amino acid residues 121 and 135 of gE. In this study, we validated that this epitope is highly conserved amongst different VZV strains that covered five existing phylogenetic clades with an identity of 100%. We evaluated the immunogenicity of the recombinant hepatitis B virus core (HBc) virus-like particles (VLPs) which included amino acids (121-135). VZV-gE-specific antibodies were detected in immunized mouse serum using ELISA. The anti-peptide antiserum positively detected VZV via Western blot and immunofluorescent staining assays. More importantly, these peptides could neutralize VZV, indicating that these peptides represented neutralizing epitopes. These findings have important implications for the development of epitope-based protective VZV vaccines.

  11. Collision induced dissociation of doubly-charged ions: Coulomb explosion vs. neutral loss in [Ca(urea)]{sup 2+} gas phase unimolecular reactivity via chemical dynamics simulations

    SciTech Connect

    Spezia, Riccardo; Salpin, Jean-Yves; Cimas, Alvaro; Gaigeot, Marie-Pierre; Song, Kihyung; Hase, William L.

    2012-07-01

    In this paper we report different theoretical approaches to study the gas-phase unimolecular dissociation of the doubly-charged cation [Ca(urea)]{sup 2+}, in order to rationalize recent experimental findings. Quantum mechanical plus molecular mechanical (QM/MM) direct chemical dynamics simulations were used to investigate collision induced dissociation (CID) and rotational-vibrational energy transfer for Ar{sup +} [Ca(urea)]{sup 2+} collisions. For the picosecond time-domain of the simulations, both neutral loss and Coulomb explosion reactions were found and the differences in their mechanisms elucidated. The loss of neutral urea subsequent to collision with Ar occurs via a shattering mechanism, while the formation of two singly-charged cations follows statistical (or almost statistical) dynamics. Vibrational-rotational energy transfer efficiencies obtained for trajectories that do not dissociate during the trajectory integration were used in conjunction with RRKM rate constants to approximate dissociation pathways assuming complete intramolecular vibrational energy redistribution (IVR) and statistical dynamics. This statistical limit predicts, as expected, that at long time the most stable species on the potential energy surface (PES) dominate. These results, coupled with experimental CID from which both neutral loss and Coulomb explosion products were obtained, show that the gas phase dissociation of this ion occurs by multiple mechanisms leading to different products and that reactivity on the complicated PES is dynamically complex. (authors)

  12. Cold-adapted digestive aspartic protease of the clawed lobsters Homarus americanus and Homarus gammarus: biochemical characterization.

    PubMed

    Rojo, Liliana; García-Carreño, Fernando; de Los Angeles Navarrete del Toro, Maria

    2013-02-01

    Aspartic proteinases in the gastric fluid of clawed lobsters Homarus americanus and Homarus gammarus were isolated to homogeneity by single-step pepstatin-A affinity chromatography; such enzymes have been previously identified as cathepsin D-like enzymes based on their deduced amino acid sequence. Here, we describe their biochemical characteristics; the properties of the lobster enzymes were compared with those of its homolog, bovine cathepsin D, and found to be unique in a number of ways. The lobster enzymes demonstrated hydrolytic activity against synthetic and natural substrates at a wider range of pH; they were more temperature-sensitive, showed no changes in the K(M) value at 4°C, 10°C, and 25°C, and had 20-fold higher k(cat)/K(M) values than bovine enzyme. The bovine enzyme was temperature-dependent. We propose that both properties arose from an increase in molecular flexibility required to compensate for the reduction of reaction rates at low habitat temperatures. This is supported by the fast denaturation rates induced by temperature. PMID:22648335

  13. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    PubMed

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis.

  14. Grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) prevent trabecular bone loss during disuse (hibernation).

    PubMed

    McGee-Lawrence, Meghan E; Wojda, Samantha J; Barlow, Lindsay N; Drummer, Thomas D; Castillo, Alesha B; Kennedy, Oran; Condon, Keith W; Auger, Janene; Black, Hal L; Nelson, O Lynne; Robbins, Charles T; Donahue, Seth W

    2009-12-01

    Disuse typically causes an imbalance in bone formation and bone resorption, leading to losses of cortical and trabecular bone. In contrast, bears maintain balanced intracortical remodeling and prevent cortical bone loss during disuse (hibernation). Trabecular bone, however, is more detrimentally affected than cortical bone in other animal models of disuse. Here we investigated the effects of hibernation on bone remodeling, architectural properties, and mineral density of grizzly bear (Ursus arctos horribilis) and black bear (Ursus americanus) trabecular bone in several skeletal locations. There were no differences in bone volume fraction or tissue mineral density between hibernating and active bears or between pre- and post-hibernation bears in the ilium, distal femur, or calcaneus. Though indices of cellular activity level (mineral apposition rate, osteoid thickness) decreased, trabecular bone resorption and formation indices remained balanced in hibernating grizzly bears. These data suggest that bears prevent bone loss during disuse by maintaining a balance between bone formation and bone resorption, which consequently preserves bone structure and strength. Further investigation of bone metabolism in hibernating bears may lead to the translation of mechanisms preventing disuse-induced bone loss in bears into novel treatments for osteoporosis. PMID:19703606

  15. Correlation of protection against Japanese encephalitis virus and JE vaccine (IXIARO(®)) induced neutralizing antibody titers.

    PubMed

    Van Gessel, Yvonne; Klade, Christoph S; Putnak, Robert; Formica, Alessandra; Krasaesub, Somporn; Spruth, Martin; Cena, Bruno; Tungtaeng, Anchalee; Gettayacamin, Montip; Dewasthaly, Shailesh

    2011-08-11

    Immune sera from volunteers vaccinated in a blinded Phase 3 clinical trial with JE-VAX(®) and a new Japanese encephalitis virus (JEV) vaccine (IC51 or IXIARO), were tested for the ability to protect mice against lethal JEV challenge. Sera from IXIARO vaccinated subjects were pooled into four batches based on neutralizing antibody measured by plaque reduction neutralization test (PRNT(50) titer): high (∼200), medium (∼40-50), low (∼20) and negative (<10). Pooled sera from JE-VAX(®) vaccinated subjects (PRNT(50) titer∼55) and pooled JEV antibody negative pre-vaccination sera were used as controls. Groups of ten 6- to 7-week-old female ICR mice were injected intraperitoneally with 0.5 ml of each serum pool diluted 1:2 or 1:10, challenged approximately 18 h later with a lethal dose of either JEV strain SA14 (genotype III) or strain KE-093 (genotype I) and observed for 21 days. All mice in the non-immune serum groups developed clinical signs consistent with JEV infection or died, whereas high titer sera from both IXIARO and JE-VAX(®) sera protected 90-100% of the animals. Statistical tests showed similar protection against both JEV strains SA14 and KE-093 and protection correlated with the anti-JEV antibody titer of IXIARO sera as measured by PRNT(50). Ex vivo neutralizing antibody titers showed that almost all mice with a titer of 10 or greater were fully protected. In a separate study, analysis of geometric mean titers (GMTs) of the groups of mice vaccinated with different doses of IXIARO and challenged with JEV SA14 provided additional evidence that titers≥10 were protective.

  16. Neutral Atmospheres

    NASA Astrophysics Data System (ADS)

    Mueller-Wodarg, I. C. F.; Strobel, D. F.; Moses, J. I.; Waite, J. H.; Crovisier, J.; Yelle, R. V.; Bougher, S. W.; Roble, R. G.

    This paper summarizes the understanding of aeronomy of neutral atmospheres in the solar system, discussing most planets as well as Saturn's moon Titan and comets. The thermal structure and energy balance is compared, highlighting the principal reasons for discrepancies amongst the atmospheres, a combination of atmospheric composition, heliocentric distance and other external energy sources not common to all. The composition of atmospheres is discussed in terms of vertical structure, chemistry and evolution. The final section compares dynamics in the upper atmospheres of most planets and highlights the importance of vertical dynamical coupling as well as magnetospheric forcing in auroral regions, where present. It is shown that a first order understanding of neutral atmospheres has emerged over the past decades, thanks to the combined effects of spacecraft and Earth-based observations as well as advances in theoretical modeling capabilities. Key gaps in our understanding are highlighted which ultimately call for a more comprehensive programme of observation and laboratory measurements.

  17. Neutral Atmospheres

    NASA Astrophysics Data System (ADS)

    Mueller-Wodarg, I. C. F.; Strobel, D. F.; Moses, J. I.; Waite, J. H.; Crovisier, J.; Yelle, R. V.; Bougher, S. W.; Roble, R. G.

    2008-08-01

    This paper summarizes the understanding of aeronomy of neutral atmospheres in the solar system, discussing most planets as well as Saturn’s moon Titan and comets. The thermal structure and energy balance is compared, highlighting the principal reasons for discrepancies amongst the atmospheres, a combination of atmospheric composition, heliocentric distance and other external energy sources not common to all. The composition of atmospheres is discussed in terms of vertical structure, chemistry and evolution. The final section compares dynamics in the upper atmospheres of most planets and highlights the importance of vertical dynamical coupling as well as magnetospheric forcing in auroral regions, where present. It is shown that a first order understanding of neutral atmospheres has emerged over the past decades, thanks to the combined effects of spacecraft and Earth-based observations as well as advances in theoretical modeling capabilities. Key gaps in our understanding are highlighted which ultimately call for a more comprehensive programme of observation and laboratory measurements.

  18. Neutralization of (NK-cell-derived) B-cell activating factor by Belimumab restores sensitivity of chronic lymphoid leukemia cells to direct and Rituximab-induced NK lysis.

    PubMed

    Wild, J; Schmiedel, B J; Maurer, A; Raab, S; Prokop, L; Stevanović, S; Dörfel, D; Schneider, P; Salih, H R

    2015-08-01

    Natural killer (NK) cells are cytotoxic lymphocytes that substantially contribute to the therapeutic benefit of antitumor antibodies like Rituximab, a crucial component in the treatment of B-cell malignancies. In chronic lymphocytic leukemia (CLL), the ability of NK cells to lyse the malignant cells and to mediate antibody-dependent cellular cytotoxicity upon Fc receptor stimulation is compromised, but the underlying mechanisms are largely unclear. We report here that NK-cells activation-dependently produce the tumor necrosis factor family member 'B-cell activating factor' (BAFF) in soluble form with no detectable surface expression, also in response to Fc receptor triggering by therapeutic CD20-antibodies. BAFF in turn enhanced the metabolic activity of primary CLL cells and impaired direct and Rituximab-induced lysis of CLL cells without affecting NK reactivity per se. The neutralizing BAFF antibody Belimumab, which is approved for treatment of systemic lupus erythematosus, prevented the effects of BAFF on the metabolism of CLL cells and restored their susceptibility to direct and Rituximab-induced NK-cell killing in allogeneic and autologous experimental systems. Our findings unravel the involvement of BAFF in the resistance of CLL cells to NK-cell antitumor immunity and Rituximab treatment and point to a benefit of combinatory approaches employing BAFF-neutralizing drugs in B-cell malignancies.

  19. Broadly Neutralizing Hemagglutinin Stalk-Specific Antibodies Induce Potent Phagocytosis of Immune Complexes by Neutrophils in an Fc-Dependent Manner

    PubMed Central

    Mullarkey, Caitlin E.; Bailey, Mark J.; Golubeva, Diana A.; Tan, Gene S.; Nachbagauer, Raffael; He, Wenqian; Novakowski, Kyle E.; Bowdish, Dawn M.; Miller, Matthew S.

    2016-01-01

    ABSTRACT Broadly neutralizing antibodies that recognize the conserved hemagglutinin (HA) stalk have emerged as exciting new biotherapeutic tools to combat seasonal and pandemic influenza viruses. Our general understanding of the mechanisms by which stalk-specific antibodies achieve protection is rapidly evolving. It has recently been demonstrated that broadly neutralizing HA stalk-specific IgG antibodies require Fc-Fcγ receptor (FcγR) interactions for optimal protection in vivo. Here we examine the neutrophil effector functions induced by stalk-specific antibodies. As the most abundant subset of blood leukocytes, neutrophils represent a critical innate effector cell population and serve an instrumental role in orchestrating downstream adaptive responses to influenza virus infection. Yet, the interplay of HA stalk-specific IgG, Fc-FcγR engagement, and neutrophils has remained largely uncharacterized. Using an in vitro assay to detect the production of reactive oxygen species (ROS), we show that human and mouse monoclonal HA stalk-specific IgG antibodies are able to induce the production of ROS by neutrophils, while HA head-specific antibodies do not. Furthermore, our results indicate that the production of ROS is dependent on Fc receptor (FcR) engagement and phagocytosis. We went on to assess the ability of monoclonal HA stalk-specific IgA antibodies to induce ROS. Consistent with our findings for monoclonal IgGs, only HA stalk-specific IgA antibodies elicited ROS production by neutrophils. This induction is dependent on the engagement of FcαR1. Taken together, our findings describe a novel FcR-dependent effector function induced by HA stalk-specific IgG and IgA antibodies, and importantly, our studies shed light on the mechanisms by which HA stalk-specific antibodies achieve protection. PMID:27703076

  20. A live attenuated H7N7 candidate vaccine virus induces neutralizing antibody that confers protection from challenge in mice, ferrets, and monkeys.

    PubMed

    Min, Ji-Young; Vogel, Leatrice; Matsuoka, Yumiko; Lu, Bin; Swayne, David; Jin, Hong; Kemble, George; Subbarao, Kanta

    2010-11-01

    A live attenuated H7N7 candidate vaccine virus was generated by reverse genetics using the modified hemagglutinin (HA) and neuraminidase (NA) genes of highly pathogenic (HP) A/Netherlands/219/03 (NL/03) (H7N7) wild-type (wt) virus and the six internal protein genes of the cold-adapted (ca) A/Ann Arbor/6/60 ca (AA ca) (H2N2) virus. The reassortant H7N7 NL/03 ca vaccine virus was temperature sensitive and attenuated in mice, ferrets, and African green monkeys (AGMs). Intranasal (i.n.) administration of a single dose of the H7N7 NL/03 ca vaccine virus fully protected mice from lethal challenge with homologous and heterologous H7 viruses from Eurasian and North American lineages. Two doses of the H7N7 NL/03 ca vaccine induced neutralizing antibodies in serum and provided complete protection from pulmonary replication of homologous and heterologous wild-type H7 challenge viruses in mice and ferrets. One dose of the H7N7 NL/03 ca vaccine elicited an antibody response in one of three AGMs that was completely protected from pulmonary replication of the homologous wild-type H7 challenge virus. The contribution of CD8(+) and/or CD4(+) T cells to the vaccine-induced protection of mice was evaluated by T-cell depletion; T lymphocytes were not essential for the vaccine-induced protection from lethal challenge with H7 wt viruses. Additionally, passively transferred neutralizing antibody induced by the H7N7 NL/03 ca virus protected mice from lethality following challenge with H7 wt viruses. The safety, immunogenicity, and efficacy of the H7N7 NL/03 ca vaccine virus in mice, ferrets, and AGMs support the evaluation of this vaccine virus in phase I clinical trials. PMID:20810733

  1. Photon-induced Formation of Molecular Hydrogen from a Neutral Polycyclic Aromatic Hydrocarbon: 9,10-dihydroanthracene

    NASA Astrophysics Data System (ADS)

    Fu, Yi; Szczepanski, Jan; Polfer, Nick C.

    2012-01-01

    Experimental results from infrared spectroscopy and mass spectrometry provide compelling evidence that UV irradiation of the neutral polycyclic aromatic hydrocarbon (PAH) 9,10-dihydroanthracene (DHA), trapped in solid argon (12 K), results in efficient (i.e., 90% yield) conversion to anthracene and molecular hydrogen. A number of dissociation pathways involving single or double hydrogen loss are investigated computationally. Among these, two mechanisms are most credible for a one-photon dissociation process involving UV photons <5.5 eV. For the lowest-energy pathway (2.3 eV), a simultaneous lengthening of the C-H bonds of H9 and H10 gives rise to an anthracene-H2 complex. A higher-energy mechanism (3.4 eV) involves an initial lengthening of the H9 C-H bond, followed by this hydrogen "grabbing" H10, and forming H2. The high yield of this photolysis reaction suggests that similar reactions may take place for other neutral PAHs, with implications for the formation of molecular hydrogen in regions of low UV exposure, such as in dark clouds.

  2. Pre-sheath density drop induced by ion-neutral friction along plasma blobs and implications for blob velocities

    SciTech Connect

    Furno, I.; Chabloz, V.; Fasoli, A.; Loizu, J.; Theiler, C.

    2014-01-15

    The pre-sheath density drop along the magnetic field in field-aligned, radially propagating plasma blobs is investigated in the TORPEX toroidal experiment [Fasoli et al., Plasma Phys. Controlled Fusion 52, 124020 (2010)]. Using Langmuir probes precisely aligned along the magnetic field, we measure the density n{sub se} at a poloidal limiter, where blobs are connected, and the upstream density n{sub 0} at a location half way to the other end of the blobs. The pre-sheath density drop n{sub se}/n{sub 0} is then computed and its dependence upon the neutral background gas pressure is studied. At low neutral gas pressures, the pre-sheath density drop is ≈0.4, close to the value of 0.5 expected in the collisionless case. In qualitative agreement with a simple model, this value decreases with increasing gas pressure. No significant dependence of the density drop upon the radial distance into the limiter shadow is observed. The effect of reduced blob density near the limiter on the blob radial velocity is measured and compared with predictions from a blob speed-versus-size scaling law [Theiler et al., Phys. Rev. Lett. 103, 065001 (2009)].

  3. PHOTON-INDUCED FORMATION OF MOLECULAR HYDROGEN FROM A NEUTRAL POLYCYCLIC AROMATIC HYDROCARBON: 9,10-DIHYDROANTHRACENE

    SciTech Connect

    Fu Yi; Szczepanski, Jan; Polfer, Nick C.

    2012-01-01

    Experimental results from infrared spectroscopy and mass spectrometry provide compelling evidence that UV irradiation of the neutral polycyclic aromatic hydrocarbon (PAH) 9,10-dihydroanthracene (DHA), trapped in solid argon (12 K), results in efficient (i.e., 90% yield) conversion to anthracene and molecular hydrogen. A number of dissociation pathways involving single or double hydrogen loss are investigated computationally. Among these, two mechanisms are most credible for a one-photon dissociation process involving UV photons <5.5 eV. For the lowest-energy pathway (2.3 eV), a simultaneous lengthening of the C-H bonds of H9 and H10 gives rise to an anthracene-H{sub 2} complex. A higher-energy mechanism (3.4 eV) involves an initial lengthening of the H9 C-H bond, followed by this hydrogen 'grabbing' H10, and forming H{sub 2}. The high yield of this photolysis reaction suggests that similar reactions may take place for other neutral PAHs, with implications for the formation of molecular hydrogen in regions of low UV exposure, such as in dark clouds.

  4. Mucosal immunization induces a higher level of lasting neutralizing antibody response in mice by a replication-competent smallpox vaccine: vaccinia Tiantan strain.

    PubMed

    Lu, Bin; Yu, Wenbo; Huang, Xiaoxing; Wang, Haibo; Liu, Li; Chen, Zhiwei

    2011-01-01

    The possible bioterrorism threat using the variola virus, the causative agent of smallpox, has promoted us to further investigate the immunogenicity profiles of existing vaccines. Here, we study for the first time the immunogenicity profile of a replication-competent smallpox vaccine (vaccinia Tiantan, VTT strain) for inducing neutralizing antibodies (Nabs) through mucosal vaccination, which is noninvasive and has a critical implication for massive vaccination programs. Four different routes of vaccination were tested in parallel including intramuscular (i.m.), intranasal (i.n.), oral (i.o.), and subcutaneous (s.c.) inoculations in mice. We found that one time vaccination with an optimal dose of VTT was able to induce anti-VTT Nabs via each of the four routes. Higher levels of antiviral Nabs, however, were induced via the i.n. and i.o. inoculations when compared with the i.m. and s.c. routes. Moreover, the i.n. and i.o. vaccinations also induced higher sustained levels of Nabs overtime, which conferred better protections against homologous or alternating mucosal routes of viral challenges six months post vaccination. The VTT-induced immunity via all four routes, however, was partially effective against the intramuscular viral challenge. Our data have implications for understanding the potential application of mucosal smallpox vaccination and for developing VTT-based vaccines to overcome preexisting antivaccinia immunity.

  5. Cholesterol-Dependent Membrane Fusion Induced by the gp41 Membrane-Proximal External Region–Transmembrane Domain Connection Suggests a Mechanism for Broad HIV-1 Neutralization

    PubMed Central

    Apellániz, Beatriz; Rujas, Edurne; Carravilla, Pablo; Requejo-Isidro, José; Huarte, Nerea

    2014-01-01

    ABSTRACT The HIV-1 glycoprotein 41 promotes fusion of the viral membrane with that of the target cell. Structural, biochemical, and biophysical studies suggest that its membrane-proximal external region (MPER) may interact with the HIV-1 membrane and induce its disruption and/or deformation during the process. However, the high cholesterol content of the envelope (ca. 40 to 50 mol%) imparts high rigidity, thereby acting against lipid bilayer restructuring. Here, based on the outcome of vesicle stability assays, all-atom molecular dynamics simulations, and atomic force microscopy observations, we propose that the conserved sequence connecting the MPER with the N-terminal residues of the transmembrane domain (TMD) is involved in HIV-1 fusion. This junction would function by inducing phospholipid protrusion and acyl-chain splay in the cholesterol-enriched rigid envelope. Supporting the functional relevance of such a mechanism, membrane fusion was inhibited by the broadly neutralizing 4E10 antibody but not by a nonneutralizing variant with the CDR-H3 loop deleted. We conclude that the MPER-TMD junction embodies an envelope-disrupting C-terminal fusion peptide that can be targeted by broadly neutralizing antibodies. IMPORTANCE Fusion of the cholesterol-enriched viral envelope with the cell membrane marks the beginning of the infectious HIV-1 replicative cycle. Consequently, the Env glycoprotein-mediated fusion function constitutes an important clinical target for inhibitors and preventive vaccines. Antibodies 4E10 and 10E8 bind to one Env vulnerability site located at the gp41 membrane-proximal external region (MPER)–transmembrane domain (TMD) junction and block infection. These antibodies display broad viral neutralization, which underscores the conservation and functionality of the MPER-TMD region. In this work, we combined biochemical assays with molecular dynamics simulations and microscopy observations to characterize the unprecedented fusogenic activity of the

  6. Chimeric gag-V3 virus-like particles of human immunodeficiency virus induce virus-neutralizing antibodies.

    PubMed Central

    Luo, L; Li, Y; Cannon, P M; Kim, S; Kang, C Y

    1992-01-01

    A 41-kDa unprocessed human immunodeficiency virus 2 (HIV-2) gag precursor protein that has a deletion of a portion of the viral protease assembles as virus-like particles by budding through the cytoplasmic membrane of recombinant baculovirus-infected insect cells. We have constructed six different combinations of chimeric genes by coupling the truncated HIV-2 gag gene to the neutralizing domain (V3) or the neutralizing and the CD4 binding domains (V3+CD4BD) of gp120 env gene sequences from HIV-1 or HIV-2. The env gene sequences were inserted either into the middle of the gag gene or at the 3' terminus of the gag gene. Virus-like particles were formed by chimeric gene products only when the env gene sequences were linked to the 3' terminus of the gag gene. Insertion of env gene sequence in the middle of the gag gene resulted in high-level chimeric gene expression but without the formation of virus-like particles. Three different chimeric genes [gag gene with HIV-1 V3 (1V3), gag gene with HIV-2 V3 (2V3), and gag gene with HIV-2 V3+CD4BD (2V3+CD4BD)] formed virus-like particles that were secreted into the cell culture medium. In contrast, the HIV-1 V3+CD4BD/HIV-2 gag construct did not form virus-like particles. The chimeric gag-env particles had spherical morphology and the size was slightly larger than that of the gag particles, but the chimeric particles were similar to the mature HIV particles. Western blot analysis showed that the gag-env chimeric proteins were recognized by antibodies in HIV-positive human serum and rabbit anti-gp120 serum. Rabbit anti-gag 1V3 and anti-gag 2V3 sera reacted with authentic gp120 of HIV-1 and HIV-2, respectively, and neutralized homologous HIV infectivity. Our results show that precursor gag protein has potential as a carrier for the presentation of foreign epitopes in good immunological context. The gag protein is highly immunogenic and has the ability to carry large foreign inserts; as such, it offers an attractive approach for

  7. Modified sugar beet pectin induces apoptosis of colon cancer cells via an interaction with the neutral sugar side-chains.

    PubMed

    Maxwell, Ellen G; Colquhoun, Ian J; Chau, Hoa K; Hotchkiss, Arland T; Waldron, Keith W; Morris, Victor J; Belshaw, Nigel J

    2016-01-20

    Pectins extracted from a variety of sources and modified with heat and/or pH have previously been shown to exhibit activity towards several cancer cell lines. However, the structural basis for the anti-cancer activity of modified pectin requires clarification. Sugar beet and citrus pectin extracts have been compared. Pectin extracted from sugar beet pulp only weakly affected the viability of colon cancer cells. Alkali treatment increased the anti-cancer effect of sugar beet pectin via an induction of apoptosis. Alkali treatment decreased the degree of esterification (DE) and increased the ratio of rhamnogalacturonan I (RGI) to homogalacturonan. Low DE per se did not play a significant role in the anti-cancer activity. However, the enzymatic removal of galactose and, to a lesser extent, arabinose from the pectin decreased the effect on cancer cells indicating that the neutral sugar-containing RGI regions are important for pectin bioactivity.

  8. Modified sugar beet pectin induces apoptosis of colon cancer cells via an interaction with the neutral sugar side-chains.

    PubMed

    Maxwell, Ellen G; Colquhoun, Ian J; Chau, Hoa K; Hotchkiss, Arland T; Waldron, Keith W; Morris, Victor J; Belshaw, Nigel J

    2016-01-20

    Pectins extracted from a variety of sources and modified with heat and/or pH have previously been shown to exhibit activity towards several cancer cell lines. However, the structural basis for the anti-cancer activity of modified pectin requires clarification. Sugar beet and citrus pectin extracts have been compared. Pectin extracted from sugar beet pulp only weakly affected the viability of colon cancer cells. Alkali treatment increased the anti-cancer effect of sugar beet pectin via an induction of apoptosis. Alkali treatment decreased the degree of esterification (DE) and increased the ratio of rhamnogalacturonan I (RGI) to homogalacturonan. Low DE per se did not play a significant role in the anti-cancer activity. However, the enzymatic removal of galactose and, to a lesser extent, arabinose from the pectin decreased the effect on cancer cells indicating that the neutral sugar-containing RGI regions are important for pectin bioactivity. PMID:26572430

  9. H5N1 Whole-Virus Vaccine Induces Neutralizing Antibodies in Humans Which Are Protective in a Mouse Passive Transfer Model

    PubMed Central

    Howard, M. Keith; Sabarth, Nicolas; Savidis-Dacho, Helga; Portsmouth, Daniel; Kistner, Otfried; Kreil, Thomas R.; Ehrlich, Hartmut J.; Barrett, P. Noel

    2011-01-01

    Background Vero cell culture-derived whole-virus H5N1 vaccines have been extensively tested in clinical trials and consistently demonstrated to be safe and immunogenic; however, clinical efficacy is difficult to evaluate in the absence of wide-spread human disease. A lethal mouse model has been utilized which allows investigation of the protective efficacy of active vaccination or passive transfer of vaccine induced sera following lethal H5N1 challenge. Methods We used passive transfer of immune sera to investigate antibody-mediated protection elicited by a Vero cell-derived, non-adjuvanted inactivated whole-virus H5N1 vaccine. Mice were injected intravenously with H5N1 vaccine-induced rodent or human immune sera and subsequently challenged with a lethal dose of wild-type H5N1 virus. Results Passive transfer of H5N1 vaccine-induced mouse, guinea pig and human immune sera provided dose-dependent protection of recipient mice against lethal challenge with wild-type H5N1 virus. Protective dose fifty values for serum H5N1 neutralizing antibody titers were calculated to be ≤1∶11 for all immune sera, independently of source species. Conclusions These data underpin the confidence that the Vero cell culture-derived, whole-virus H5N1 vaccine will be effective in a pandemic situation and support the use of neutralizing serum antibody titers as a correlate of protection for H5N1 vaccines. PMID:21876771

  10. An immunogen containing four tandem 10E8 epitope repeats with exposed key residues induces antibodies that neutralize HIV-1 and activates an ADCC reporter gene.

    PubMed

    Sun, Zhiwu; Zhu, Yun; Wang, Qian; Ye, Ling; Dai, Yanyan; Su, Shan; Yu, Fei; Ying, Tianlei; Yang, Chinglai; Jiang, Shibo; Lu, Lu

    2016-01-01

    After three decades of intensive research efforts, an effective vaccine against HIV-1 remains to be developed. Several broadly neutralizing antibodies to HIV-1, such as 10E8, recognize the membrane proximal external region (MPER) of the HIV-1 gp41 protein. Thus, the MPER is considered to be a very important target for vaccine design. However, the MPER segment has very weak immunogenicity and tends to insert its epitope residues into the cell membrane, thereby avoiding antibody binding. To address this complication in vaccine development, we herein designed a peptide, designated 10E8-4P, containing four copies of the 10E8 epitope as an immunogen. As predicted by structural simulation, 10E8-4P exhibits a well-arranged tandem helical conformation, with the key residues in the 10E8 epitope oriented at different angles, thus suggesting that some of these key residues may be exposed outside of the lipid membrane. Compared with a peptide containing a single 10E8 epitope (10E8-1P), 10E8-4P not only exhibited better antigenicity but also elicited neutralizing antibody response against HIV-1 pseudoviruses, whereas 10E8-1P could not induce detectable neutralizing antibody response. Importantly, antibodies elicited by 10E8-4P also possessed a strong ability to activate an antibody-dependent cell-mediated cytotoxicity (ADCC) reporter gene, thus suggesting that they may have ADCC activity. Therefore, this strategy shows promise for further optimization and application in future HIV-1 vaccine design. PMID:27329850

  11. Neutral atom traps.

    SciTech Connect

    Pack, Michael Vern

    2008-12-01

    This report describes progress in designing a neutral atom trap capable of trapping sub millikelvin atom in a magnetic trap and shuttling the atoms across the atom chip from a collection area to an optical cavity. The numerical simulation and atom chip design are discussed. Also, discussed are preliminary calculations of quantum noise sources in Kerr nonlinear optics measurements based on electromagnetically induced transparency. These types of measurements may be important for quantum nondemolition measurements at the few photon limit.

  12. Consumption of seeds of southwestern white pine (Pinus strobiformis) by Black Bear (Ursus americanus)

    USGS Publications Warehouse

    Mattson, David J.; Arundel, Terry A.

    2013-01-01

    We report a discovery of black bears (Ursus americanus) consuming seeds of southwestern white pine (Pinus strobiformis) on north slopes of the San Francisco Peaks near Flagstaff, Arizona, in high-elevation, mixed-species conifer forest. In one instance, a bear had obtained seeds from cones excavated from a larder horde made by a red squirrel (Tamiasciurus hudsonicus). Consumption of seeds of southwestern white pine by bears had not been previously documented. This discovery adds to the number of species of pine used by bears for food as well as the geographic range within which the behavior occurs.

  13. Mediastinal teratoma in a free-ranging American black bear (Ursus americanus).

    PubMed

    Munk, Brandon A; Turner, J Chris; Keel, M Kevin

    2013-12-01

    A 2.75-yr-old female American black bear (Ursus americanus) was found emaciated and unable to rise. It was euthanized due to the perceived poor prognosis. An approximately 18 x 8 x 10-cm, multiloculated, well-demarcated mass that extended from the bifurcation of the trachea, laterally displacing the lung lobes and caudally displacing the heart. The mass contained fibrous connective tissue, cartilage, bone, nervous tissue, smooth muscle, and a variety of epithelial structures. A mediastinal teratoma was diagnosed based on the microscopic features of the neoplasm. PMID:24450083

  14. SURGICAL CORRECTION OF BILATERAL PATELLAR LUXATION IN AN AMERICAN BLACK BEAR CUB (URSUS AMERICANUS).

    PubMed

    Bennett, Katarina R; Desmarchelier, Marion R; Bailey, Trina R

    2015-06-01

    A wild orphaned male American black bear cub ( Ursus americanus ) presented with hind limb gait abnormalities and was found to have bilateral grade 3 laterally luxating patellas. There were no other significant abnormalities detected on neurologic, radiographic, or hematologic examinations. The trochlear grooves were deepened with a chondroplasty, and the redundant soft tissues imbricated. There was a marked improvement in the bear's gait postoperatively, with an apparent full return to function. To the authors' knowledge, patellar luxation has not been reported in the Ursidae family, and the success in this case suggests that this technique may be used in large wild or captive carnivore cubs. PMID:26056894

  15. Studies on endoparasites of the black bear (Ursus americanus) in the southeastern United States.

    PubMed

    Crum, J M; Nettles, V F; Davidson, W R

    1978-04-01

    Examination of 53 black bears (Ursus americanus) from six states in the southeastern United States revealed at least 17 species of endoparasites, including Sarcocystis sp., Spirometra mansonoides (spargana), Macracanthorhynchus ingens, Ancylostoma caninum, Arthrocephalus lotoris, Baylisascaris transfuga, Capillaria aerophila, Capillaria putorii, Crenosoma sp., Cyathospirura sp., Dirofilaria immitis, Gnathostoma sp., Gongylonema pulchrum, microfilariae, Molineus barbatus, Physaloptera sp. and Strongyloides sp. Twelve of these represent new host records for black bear, and two are considered to be new species. Data are presented on prevalence, intensity and geographic distribution of each species. Pathologic effects were associated with infections of spargana of S. mansonoides and adults of C. aerophilia.

  16. Peste des petits ruminants virus-like particles induce both complete virus-specific antibodies and virus neutralizing antibodies in mice.

    PubMed

    Liu, Fuxiao; Wu, Xiaodong; Zou, Yanli; Li, Lin; Wang, Zhiliang

    2015-03-01

    Peste des petits ruminants virus (PPRV), an etiological agent of peste des petits ruminants (PPR), is classified into the genus Morbillivirus in the family Paramyxoviridae. In a previous study, a recombinant baculovirus has been constructed to co-express the PPRV matrix (M), haemagglutinin (H) and nucleocapsid (N) proteins in insect cells, causing budding of PPR virus-like particles (VLPs) from insect cell membranes by viewing of ultrathin section with a transmission electron microscope. In this follow-up study, these PPR VLPs were purified by sucrose density gradient centrifugation for immunizing mice twice. Three weeks post-primary immunization and 2 weeks post-secondary immunization, all serum samples were obtained and subsequently subjected to indirect ELISA detection on complete virus-specific antibodies. In addition, all serum samples, which were collected 2 weeks post-secondary immunization, were used for virus neutralization test on PPRV neutralizing antibodies. The results showed that the purified PPR VLPs induced both types of antibodies mentioned above in mice, indicating a given potential of VLP-based vaccine candidate against PPR. PMID:25486084

  17. ELPylated haemagglutinins produced in tobacco plants induce potentially neutralizing antibodies against H5N1 viruses in mice.

    PubMed

    Phan, Hoang T; Pohl, Julia; Floss, Doreen M; Rabenstein, Frank; Veits, Jutta; Le, Binh T; Chu, Ha H; Hause, Gerd; Mettenleiter, Thomas; Conrad, Udo

    2013-06-01

    Reducing the cost of vaccine production is a key priority for veterinary research, and the possibility of heterologously expressing antigen in plants provides a particularly attractive means of achieving this. Here, we report the expression of the avian influenza virus haemagglutinin (AIV HA) in tobacco, both as a monomer and as a trimer in its native and its ELPylated form. We firstly presented evidence to produce stabilized trimers of soluble HA in plants. ELPylation of these trimers does not influence the trimerization. Strong expression enhancement in planta caused by ELPylation was demonstrated for trimerized H5-ELP. ELPylated trimers could be purified by a membrane-based inverse transition cycling procedure with the potential of successful scale-up. The trimeric form of AIV HA was found to enhance the HA-specific immune response compared with the monomeric form. Plant-derived AIV HA trimers elicited potentially neutralizing antibodies interacting with both homologous virus-like particles from plants and heterologous inactivated AIV. ELPylation did not influence the functionality and the antigenicity of the stabilized H5 trimers. These data allow further developments including scale-up of production, purification and virus challenge experiments with the final goal to achieve suitable technologies for efficient avian flu vaccine production.

  18. Pediatric Measles Vaccine Expressing a Dengue Antigen Induces Durable Serotype-specific Neutralizing Antibodies to Dengue Virus

    PubMed Central

    Brandler, Samantha; Lucas-Hourani, Marianne; Moris, Arnaud; Frenkiel, Marie-Pascale; Combredet, Chantal; Février, Michèle; Bedouelle, Hugues; Schwartz, Olivier; Desprès, Philippe; Tangy, Frédéric

    2007-01-01

    Dengue disease is an increasing global health problem that threatens one-third of the world's population. Despite decades of efforts, no licensed vaccine against dengue is available. With the aim to develop an affordable vaccine that could be used in young populations living in tropical areas, we evaluated a new strategy based on the expression of a minimal dengue antigen by a vector derived from pediatric live-attenuated Schwarz measles vaccine (MV). As a proof-of-concept, we inserted into the MV vector a sequence encoding a minimal combined dengue antigen composed of the envelope domain III (EDIII) fused to the ectodomain of the membrane protein (ectoM) from DV serotype-1. Immunization of mice susceptible to MV resulted in a long-term production of DV1 serotype-specific neutralizing antibodies. The presence of ectoM was critical to the immunogenicity of inserted EDIII. The adjuvant capacity of ectoM correlated with its ability to promote the maturation of dendritic cells and the secretion of proinflammatory and antiviral cytokines and chemokines involved in adaptive immunity. The protective efficacy of this vaccine should be studied in non-human primates. A combined measles–dengue vaccine might provide a one-shot approach to immunize children against both diseases where they co-exist. PMID:18160988

  19. Neutral Particle Analyzer Vertically Scanning Measurements of MHD-induced Energetic Ion Redistribution or Loss in the National Spherical Torus Experiment

    SciTech Connect

    S.S. Medley, R. Andre, R.E. Bell, D.S. Darrow, C.W. Domier, E.D. Fredrickson, N.N. Gorelenkov, S.M. Kaye, B.P. LeBlanc, K.C. Lee, F.M. Levinton, D. Liu, N.C. Luhmann, Jr., J.E. Menard, H. Park, D. Stutman, A.L. Roquemore, K. Tritz, H. Yuh and the NSTX Team

    2007-11-15

    Observations of magneto-hydro-dynamic (MHD) induced redistribution or loss of energetic ions measured using the vertically scanning capability of the Neutral Particle Analyzer diagnostic on the National Spherical Torus Experiment (NSTX) are presented along with TRANSP and ORBIT code analysis of the results. Although redistribution or loss of energetic ions due to bursting fishbone-like and low-frequency (f ~ 10 kHz) kinktype MHD activity has been reported previously, the primary goal of this work is to study redistribution or loss due to continuous Alfvénic (f ~ 20 – 150 kHz) modes, a topic that heretofore has not been investigated in detail for NSTX plasmas. Initial indications are that the former drive energetic ion loss whereas the continuous Alfvénic modes only cause redistribution and the energetic ions remain confined.

  20. The blood-stage malaria antigen PfRH5 is susceptible to vaccine-inducible cross-strain neutralizing antibody.

    PubMed

    Douglas, Alexander D; Williams, Andrew R; Illingworth, Joseph J; Kamuyu, Gathoni; Biswas, Sumi; Goodman, Anna L; Wyllie, David H; Crosnier, Cécile; Miura, Kazutoyo; Wright, Gavin J; Long, Carole A; Osier, Faith H; Marsh, Kevin; Turner, Alison V; Hill, Adrian V S; Draper, Simon J

    2011-12-20

    Current vaccine strategies against the asexual blood stage of Plasmodium falciparum are mostly focused on well-studied merozoite antigens that induce immune responses after natural exposure, but have yet to induce robust protection in any clinical trial. Here we compare human-compatible viral-vectored vaccines targeting ten different blood-stage antigens. We show that the full-length P. falciparum reticulocyte-binding protein homologue 5 (PfRH5) is highly susceptible to cross-strain neutralizing vaccine-induced antibodies, out-performing all other antigens delivered by the same vaccine platform. We find that, despite being susceptible to antibody, PfRH5 is unlikely to be under substantial immune selection pressure; there is minimal acquisition of anti-PfRH5 IgG antibodies in malaria-exposed Kenyans. These data challenge the widespread beliefs that any merozoite antigen that is highly susceptible to immune attack would be subject to significant levels of antigenic polymorphism, and that erythrocyte invasion by P. falciparum is a degenerate process involving a series of parallel redundant pathways.

  1. Photosensitizers neutral red (type I) and rose bengal (type II) cause light-dependent toxicity in Chlamydomonas reinhardtii and induce the Gpxh gene via increased singlet oxygen formation.

    PubMed

    Fischer, Beat B; Krieger-Liszkay, Anja; Eggen, Rik L

    2004-12-01

    The connection between the mode of toxic action and the genetic response caused by the type I photosensitizer and photosynthesis inhibitor neutral red (NR) and the type II photosensitizer rose bengal (RB) was investigated in the green alga Chlamydomonas reinhardtii. For both photosensitizers, a light intensity-dependent increase in toxicity and expression of the glutathione peroxidase homologous gene (Gpxh) was found. The toxicity of RB was reduced by the singlet oxygen (1O2) quenchers 1,4-diazabicyclo[2.2.2]octane and L-histidine, and the RB-induced Gpxh expression was stimulated in deuterium oxide-supplemented growth medium. These observations clearly indicate the involvement of 1O2 in both toxicity and the genetic response caused by RB. NR up-regulated the expression of typical oxidative and general stress response genes, probably by a type I mechanism, and also strongly induced the Gpxh expression. The stimulating effect of deuterium oxide in the growth medium suggested the involvement of 1O2 also in the NR-induced response. Indeed, an increased 1O2 formation was detected with EPR-spin trapping in NR-treated spinach thylakoids. However, none of the 102 quenchers could reduce the light-dependent toxicity of NR in C. reinhardtii, indicating that NR has a different mode of toxic action than RB.

  2. Sarcocystis sp. in mountain goats (Oreamnos americanus) in Washington: prevalence and search for the definitive host.

    PubMed

    Foreyt, W J

    1989-10-01

    During October and November 1986, Sarcocystis sp. was detected in 24 of 56 (43%) tongues from hunter-killed mountain goats (Oreamnos americanus) in Washington (USA). Sarcocysts had an unusual sessile polyp-shaped branched wall. Mean size of 154 sarcocysts was 71.3 x 37.8 microns (range, 20 to 248 x 10 to 120 microns), and the mean intensity was 2.3 (range, 1 to 28). In an attempt to identify the definitive host, infected tongues were fed to four coyotes (Canis latrans), eight domestic dogs, four domestic cats, three bears (Ursus americanus), two raccoons (Procyon lotor), two martens (Martes americana), two fishers (Martes pennanti), three skunks (Mephitis mephitis), five mink (Mustela vison), five ferrets (Mustela putorius), one pigtail macaque (Macaca nemestrina), two red-tailed hawks (Buteo jamaicensis) and one great horned owl (Bubo virginianus). Oocysts or sporocysts were not detected in the feces of any host for less than or equal to 20 days after ingestion of the infected meat. The definitive host for Sarcocystis sp. in mountain goats was not identified.

  3. Seasonal and daily plasma corticosterone rhythms in American toads, Bufo americanus

    SciTech Connect

    Pancak, M.K.; Taylor, D.H.

    1983-06-01

    Concentrations of corticosterone were measured in the plasma of American toads, Bufo americanus, on a seasonal basis using a radioimmunoassay technique. Two populations of toads, maintained under different light conditions, were monitored to observe the effects of photoperiod on the seasonal rhythm of plasma corticosterone. Under a natural photoperiod toads demonstrated a rhythm consisting of a spring peak and a fall peak in corticosterone concentration. Toads maintained under a 12L:12D photoperiod all year round demonstrated a similar rhythm with peaks in the spring and fall. This suggests that an endogenous (circannual) rhythm of corticosterone may be playing an important role in the seasonal change of overt behavior and physiology of Bufo americanus. A daily rhythm of corticosterone was also detected in toads when blood samples were taken every 4 hr. When compared to a previously published circadian rhythm study of locomotor activity, the surge in corticosterone concentration for the day occurred at 1730 just prior to the peak in locomotor activity.

  4. Aspartic cathepsin D endopeptidase contributes to extracellular digestion in clawed lobsters Homarus americanus and Homarus gammarus.

    PubMed

    Rojo, Liliana; Muhlia-Almazan, Adriana; Saborowski, Reinhard; García-Carreño, Fernando

    2010-11-01

    Acid digestive proteinases were studied in the gastric fluids of two species of clawed lobster (Homarus americanus and Homarus gammarus). An active protein was identified in both species as aspartic proteinase by specific inhibition with pepstatin A. It was confirmed as cathepsin D by mass mapping, N-terminal, and full-length cDNA sequencing. Both lobster species transcribed two cathepsin D mRNAs: cathepsin D1 and cathepsin D2. Cathepsin D1 mRNA was detected only in the midgut gland, suggesting its function as a digestive enzyme. Cathepsin D2 mRNA was found in the midgut gland, gonads, and muscle. The deduced amino acid sequence of cathepsin D1 and cathepsin D2 possesses two catalytic DTG active-site motifs, the hallmark of aspartic proteinases. The putatively active cathepsin D1 has a molecular mass of 36.4 kDa and a calculated pI of 4.14 and possesses three potential glycosylation sites. The sequences showed highest similarities with cathepsin D from insects but also with another crustacean cathepsin D. Cathepsin D1 transcripts were quantified during a starvation period using real-time qPCR. In H. americanus, 15 days of starvation did not cause significant changes, but subsequent feeding caused a 2.5-fold increase. In H. gammarus, starvation caused a 40% reduction in cathepsin D1 mRNA, and no effect was observed with subsequent feeding. PMID:20169386

  5. Cloning and expression study of the lobster (Homarus americanus) vitellogenin: Conservation in gene structure among decapods.

    PubMed

    Tiu, Shirley Hiu Kwan; Hui, Ho-Lam; Tsukimura, Brian; Tobe, Stephen S; He, Jian-Guo; Chan, Siu-Ming

    2009-01-01

    This study reports the molecular characterization of the vitellogenin (Vg) of the lobster, Homarus americanus. Based on the annual collection of female lobsters, vitellogenesis commences in early March and continues through to September of each year. Using an antibody to vitellin of the lobster, H. americanus, several immunoreactive ovarian proteins were initially identified by Western blot analysis. The 80kDa protein contained the amino acid sequence APWGGNTPRC, identified subsequently by cDNA cloning to be identical to the lobster Vg. In common with the shrimp Metapenaeus ensis and crab Charybdis feriatus, the lobster HaVg1 gene comprises 14 introns and 15 exons. The deduced HaVg1 precursor is most similar to the Vg of the crayfish Cherax quadricarinatus (57%), followed by M. ensis (40-43% identity) and C. feriatus (38%). The results from genomic and RT-PCR cloning also confirmed the presence of multiple Vg genes in lobster. At early reproductive stages, the hepatopancreas HaVg1 transcript levels are low but increased to a maximum in animals with mature oocytes. The ovary, however, also expressed low levels of HaVg1. Using in vitro explant culture, treatment of hepatopancreas fragments with farnesoic acid or 20-hydroxyecdysone resulted in a significant stimulation in HaVg1 expression. From this study, it appears that Vg gene organization and expression pattern in decapods is highly conserved. Similar endocrine mechanisms may govern the process of vitellogenesis across the decapods.

  6. Sarcocystis sp. in mountain goats (Oreamnos americanus) in Washington: prevalence and search for the definitive host.

    PubMed

    Foreyt, W J

    1989-10-01

    During October and November 1986, Sarcocystis sp. was detected in 24 of 56 (43%) tongues from hunter-killed mountain goats (Oreamnos americanus) in Washington (USA). Sarcocysts had an unusual sessile polyp-shaped branched wall. Mean size of 154 sarcocysts was 71.3 x 37.8 microns (range, 20 to 248 x 10 to 120 microns), and the mean intensity was 2.3 (range, 1 to 28). In an attempt to identify the definitive host, infected tongues were fed to four coyotes (Canis latrans), eight domestic dogs, four domestic cats, three bears (Ursus americanus), two raccoons (Procyon lotor), two martens (Martes americana), two fishers (Martes pennanti), three skunks (Mephitis mephitis), five mink (Mustela vison), five ferrets (Mustela putorius), one pigtail macaque (Macaca nemestrina), two red-tailed hawks (Buteo jamaicensis) and one great horned owl (Bubo virginianus). Oocysts or sporocysts were not detected in the feces of any host for less than or equal to 20 days after ingestion of the infected meat. The definitive host for Sarcocystis sp. in mountain goats was not identified. PMID:2509738

  7. Neutral depletion versus repletion due to ionization

    SciTech Connect

    Fruchtman, A.; Makrinich, G.; Raimbault, J.-L.; Liard, L.; Rax, J.-M.; Chabert, P.

    2008-05-15

    Recent theoretical analyses which predicted unexpected effects of neutral depletion in both collisional and collisionless plasmas are reviewed. We focus on the depletion of collisionless neutrals induced by strong ionization of a collisionless plasma and contrast this depletion with the effect of strong ionization on thermalized neutrals. The collisionless plasma is analyzed employing a kinetic description. The collisionless neutrals and the plasma are coupled through volume ionization and wall recombination only. The profiles of density and pressure both of the plasma and of the neutral-gas and the profile of the ionization rate are calculated. It is shown that for collisionless neutrals the ionization results in neutral depletion, while when neutrals are thermalized the ionization induces a maximal neutral-density at the discharge center, which we call neutral repletion. The difference between the two cases stems from the relation between the neutral density and pressure. The pressure of the collisionless neutral-gas turns out to be maximal where its density is minimal, in contrast to the case of a thermalized neutral gas.

  8. Signal enhancement of neutral He emission lines by fast electron bombardment of laser-induced He plasma

    NASA Astrophysics Data System (ADS)

    Suyanto, Hery; Pardede, Marincan; Hedwig, Rinda; Marpaung, Alion Mangasi; Ramli, Muliadi; Lie, Tjung Jie; Abdulmadjid, Syahrun Nur; Kurniawan, Koo Hendrik; Tjia, May On; Kagawa, Kiichiro

    2016-08-01

    A time-resolved spectroscopic study is performed on the enhancement signals of He gas plasma emission using nanosecond (ns) and picosecond (ps) lasers in an orthogonal configuration. The ns laser is used for the He gas plasma generation and the ps laser is employed for the ejection of fast electrons from a metal target, which serves to excite subsequently the He atoms in the plasma. The study is focused on the most dominant He I 587.6 nm and He I 667.8 nm emission lines suggested to be responsible for the He-assisted excitation (HAE) mechanism. The time-dependent intensity enhancements induced by the fast electrons generated with a series of delayed ps laser ablations are deduced from the intensity time profiles of both He emission lines. The results clearly lead to the conclusion that the metastable excited triplet He atoms are actually the species overwhelmingly produced during the recombination process in the ns laser-induced He gas plasma. These metastable He atoms are believed to serve as the major energy source for the delayed excitation of analyte atoms in ns laser-induced breakdown spectroscopy (LIBS) using He ambient gas.

  9. Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation.

    PubMed

    Iaizzo, Paul A; Laske, Timothy G; Harlow, Henry J; McClay, Carolyn B; Garshelis, David L

    2012-03-01

    Even mildly hypothermic body or limb temperatures can retard healing processes in mammals. Despite this, we observed that hibernating American black bears (Ursus americanus Pallas, 1780) elicit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. In addition, they resolve injuries during hibernation while maintaining mildly hypothermic states (30-35 °C) and without eating, drinking, urinating or defecating. We describe experimental studies on free-ranging bears that document their abilities to completely resolve cutaneous cuts and punctures incurred during or prior to hibernation. We induced small, full-thickness cutaneous wounds (biopsies or incisions) during early denning, and re-biopsied sites 2-3 months later (near the end of denning). Routine histological methods were used to characterize these skin samples. All biopsied sites with respect to secondary intention (open circular biopsies) and primary intention (sutured sites) healed, with evidence of initial eschar (scab) formation, completeness of healed epidermis and dermal layers, dyskeratosis (inclusion cysts), and abilities to produce hair follicles. These healing abilities of hibernating black bears are a clear survival advantage to animals injured before or during denning. Bears are known to have elevated levels of hibernation induction trigger (delta-opioid receptor agonist) and ursodeoxycholic acid (major bile acid within plasma, mostly conjugated with taurine) during hibernation, which may relate to these wound-healing abilities. Further research as to the underlying mechanisms of wound healing during hibernation could have applications in human medicine. Unique approaches may be found to improve healing for malnourished, hypothermic, diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries.

  10. Wound healing during hibernation by black bears (Ursus americanus) in the wild: elicitation of reduced scar formation.

    PubMed

    Iaizzo, Paul A; Laske, Timothy G; Harlow, Henry J; McClay, Carolyn B; Garshelis, David L

    2012-03-01

    Even mildly hypothermic body or limb temperatures can retard healing processes in mammals. Despite this, we observed that hibernating American black bears (Ursus americanus Pallas, 1780) elicit profound abilities in mounting inflammatory responses to infection and/or foreign bodies. In addition, they resolve injuries during hibernation while maintaining mildly hypothermic states (30-35 °C) and without eating, drinking, urinating or defecating. We describe experimental studies on free-ranging bears that document their abilities to completely resolve cutaneous cuts and punctures incurred during or prior to hibernation. We induced small, full-thickness cutaneous wounds (biopsies or incisions) during early denning, and re-biopsied sites 2-3 months later (near the end of denning). Routine histological methods were used to characterize these skin samples. All biopsied sites with respect to secondary intention (open circular biopsies) and primary intention (sutured sites) healed, with evidence of initial eschar (scab) formation, completeness of healed epidermis and dermal layers, dyskeratosis (inclusion cysts), and abilities to produce hair follicles. These healing abilities of hibernating black bears are a clear survival advantage to animals injured before or during denning. Bears are known to have elevated levels of hibernation induction trigger (delta-opioid receptor agonist) and ursodeoxycholic acid (major bile acid within plasma, mostly conjugated with taurine) during hibernation, which may relate to these wound-healing abilities. Further research as to the underlying mechanisms of wound healing during hibernation could have applications in human medicine. Unique approaches may be found to improve healing for malnourished, hypothermic, diabetic and elderly patients or to reduce scarring associated with burns and traumatic injuries. PMID:22405448

  11. Helminth community structure of sympatric eastern American toad, Bufo americanus americanus, northern leopard frog, Rana pipiens, and blue-spotted salamander, Ambystoma laterale, from southeastern Wisconsin.

    PubMed

    Bolek, Matthew G; Coggins, James R

    2003-08-01

    One-hundred twelve amphibians, including 51 blue-spotted salamanders, Ambystoma laterale, 30 eastern American toads, Bufo americanus americanus, and 31 northern leopard frogs, Rana pipiens, were collected during April-October 1996 from Waukesha County, Wisconsin and examined for helminth parasites. The helminth compound community of this amphibian assemblage consisted of at least 10 species: 9 in American toads, 8 in leopard frogs, and 3 in blue-spotted salamanders. American toads shared 7 species with leopard frogs, and 2 species occurred in all 3 host species. Although there was a high degree of helminth species overlap among these sympatric amphibians, statistically significant differences were found among host species and percent of indirect or direct-life cycle parasites of amphibian species individual component communities (chi2 = 1,015, P < 0.001). American toads had a higher relative abundance of nematodes, 59%, than larval cestodes, 31%, and larval and adult trematodes, 10%, whereas leopard frogs had a higher relative abundance of larval cestodes, 71.3%, and larval and adult trematodes, 25.3%, than nematodes 3.4%. This is related to ecological differences in habitat and dietary preferences between these 2 anuran species. Helminth communities of blue-spotted salamanders were depauperate and were dominated by larval trematodes, 94%, and few nematodes, 6%. Low helminth species richness in this host species is related to this salamander's relatively small host body size, smaller gape size, lower vagility, and more fossorial habitat preference than the other 2 anuran species. Adult leopard frogs and toads had significantly higher mean helminth species richness than metamorphs, but there was no significant difference in mean helminth species richness among adult and metamorph blue-spotted salamanders. Considering adult helminths, the low species richness and low vagility of caudatans as compared with anurans suggest that local factors may be more important in

  12. Isolation and characterization of new genetic types of toxoplasma gondii and prevalence of trichinella murrelli from black bear (Ursus americanus)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Black bears (Ursus americanus) are hosts for two important zoonotic parasites, Toxoplasma gondii and Trichinella spp. and bears are hunted for human consumption in the USA. Little is known of the genetic diversity of T. gondii circulating in wildlife. In the present study, antibodies to T. gondii we...

  13. The hidden history of the snowshoe hare, Lepus americanus: extensive mitochondrial DNA introgression inferred from multilocus genetic variation.

    PubMed

    Melo-Ferreira, José; Seixas, Fernando A; Cheng, Ellen; Mills, L Scott; Alves, Paulo C

    2014-09-01

    Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In North America, hares (Lepus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in North America - the snowshoe hare (Lepus americanus), the white-tailed jackrabbit (L. townsendii) and the black-tailed jackrabbit (L. californicus) - by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mtDNA) locus (6240 bp; 94 specimens). A multilocus-multispecies coalescent-based phylogeny suggests that L. americanus diverged ~2.7 Ma and that L. californicus and L. townsendii split more recently (~1.2 Ma). Within L. americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other North American species. While the isolation-with-migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mtDNA divergence revealed historical mtDNA introgression from L. californicus into the Pacific Northwest populations of L. americanus. This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change.

  14. A goat poxvirus-vectored peste-des-petits-ruminants vaccine induces long-lasting neutralization antibody to high levels in goats and sheep.

    PubMed

    Chen, Weiye; Hu, Sen; Qu, Linmao; Hu, Qianqian; Zhang, Qian; Zhi, Haibing; Huang, Kehe; Bu, Zhigao

    2010-07-01

    Recombinant capripoxvirus (CPV) is a promising candidate differentiating infected from vaccinated animals (DIVA) vaccine against peste-des-petits-ruminants (PPR). In order for recombinant CPV to be successfully used in the field, there should exist dependable indicators for quality control of vaccine products, surveillance and vaccination evaluation. Viral neutralization antibody (VNA) is correlated to protection against PPR and is a technically feasible indicator for this purpose. The immunogenicity of this vectored vaccine in goats and sheep, however, has not been fully evaluated. In this study, we generated two recombinant CPV viruses, rCPV-PPRVH and rCPV-PPRVF, that express PPR virus (PPRV) glycoproteins H and F, respectively. Vaccination studies with different dosages of recombinant viruses showed that rCPV-PPRVH was a more potent inducer of PPRV VNA than rCPV-PPRVF. One dose of rCPV-PPRVH was enough to seroconvert 80% of immunized sheep. A second dose induced significantly higher PPRV VNA titers. There was no significant difference in PPRV VNA responses between goats and sheep. Subcutaneous inoculation also induced a significant PPRV VNA response. PPRV VNA could be detected for over 6 months in more than 80% of vaccinated goats and sheep. Boost vaccination at 6-month intervals induced significant re-boost efficacy of PPRV VNA in goats and sheep. More over, two doses of rCPV-PPRVH could completely overcome the interference caused by pre-existing immunity to the CPV vaccine backbone in animals. Vaccination with rCPV-PPRVH also protected goats from virulent CPV challenge. Our results demonstrate that VNA can serve as a dependent indicator for effective vaccination and immune protection of animals in the field. The recombinant CPV vaccine used in our studies could be a practical and useful candidate DIVA vaccine in countries where PPR newly emerges or where stamp-out plans are yet to be implemented.

  15. Activation of neutral-sphingomyelinase, MAPKs, and p75 NTR-mediating caffeic acid phenethyl ester–induced apoptosis in C6 glioma cells

    PubMed Central

    2014-01-01

    Background Caffeic acid phenethyl ester (CAPE), a component of propolis, is reported to possess anti-inflammatory, anti-bacterial, anti-viral, and anti-tumor activities. Previously, our laboratory demonstrated the in vitro and in vivo bioactivity of CAPE and addressed the role of p53 and the p38 mitogen-activated protein kinase (MAPK) pathway in regulating CAPE-induced apoptosis in C6 glioma cells. Results C6 cancer cell lines were exposed to doses of CAPE; DNA fragmentation and MAPKs and NGF/P75NTR levels were then determined. SMase activity and ceramide content measurement as well as western blotting analyses were performed to clarify molecular changes. The present study showed that CAPE activated neutral sphingomyelinase (N-SMase), which led to the ceramide-mediated activation of MAPKs, including extracellular signal-regulated kinase (ERK), Jun N-terminus kinase (JNK), and p38 MAPK. In addition, CAPE increased the expression of nerve growth factor (NGF) and p75 neurotrophin receptor (p75NTR). The addition of an N-SMase inhibitor, GW4869, established that NGF/p75NTR was the downstream target of N-SMase/ceramide. Pretreatment with MAPK inhibitors demonstrated that MEK/ERK and JNK acted upstream and downstream, respectively, of NGF/p75NTR. Additionally, CAPE-induced caspase 3 activation and poly [ADP-ribose] polymerase cleavage were reduced by pretreatment with MAPK inhibitors, a p75NTR peptide antagonist, or GW4869. Conclusions Taken together, N-SMase activation played a pivotal role in CAPE-induced apoptosis by activation of the p38 MAPK pathway and NGF/p75NTR may explain a new role of CAPE induced apoptosis in C6 glioma. PMID:24997497

  16. The role of ion-neutral interaction in the formation of the spatial distribution of accelerated ions in the induced magnetosphere of comet 67P

    NASA Astrophysics Data System (ADS)

    Nemeth, Zoltan; Szego, Karoly; Burch, Jim; Goldstein, Ray; Mandt, , Kathleen; Mokashi, Pat

    2016-04-01

    In the spring and early summer of 2015 Rosetta observed peculiar ion events in the induced magnetosphere of comet 67P/Churyumov-Gerasimenko. These events apeared again during the dayside excursion of Rosetta, and also in the last months of 2015. In these events accelerated cometary ions dominate the ion spectra measured by the Ion Electron Sensor (IES) of the Rosetta Plasma Consortium. In the 200 eV - 2 keV energy range these ions arrive from the SW direction. During the events the main energy of the population first increases, then saturates and later decreases. We present a mechanism, which can be responsible for these events. The ions are accelerated in the outer magnetosphere then decelerated when they enter the dense inner regions of the cometary neutral atmosphere. Investigating this deceleration mechanism allows us to determine a kind of penetration depth beyond which the accelerated population cannot reach. This mechanism leads to a well-defined spatial distribution of accelerated ions of different energies, which in turn, together with CME induced contractions of the magnetosphere, explain the observed ion events.

  17. Long-lasting protective antiviral immunity induced by passive immunotherapies requires both neutralizing and effector functions of the administered monoclonal antibody.

    PubMed

    Nasser, Roudaina; Pelegrin, Mireia; Michaud, Henri-Alexandre; Plays, Marc; Piechaczyk, Marc; Gros, Laurent

    2010-10-01

    Using FrCas(E) retrovirus-infected newborn mice as a model system, we have shown recently that a long-lasting antiviral immune response essential for healthy survival emerges after a short treatment with a neutralizing (667) IgG2a isotype monoclonal antibody (MAb). This suggested that the mobilization of adaptive immunity by administered MAbs is key for the success in the long term for the MAb-based passive immunotherapy of chronic viral infections. We have addressed here whether the anti-FrCas(E) protective endogenous immunity is the mere consequence of viral propagation blunting, which would simply give time to the immune system to react, and/or to actual immunomodulation by the MAb during the treatment. To this aim, we have compared viral replication, disease progression, and antiviral immune responses between different groups of infected mice: (i) mice treated with either the 667 MAb, its F(ab')(2) fragment, or an IgM (672) with epitopic specificity similar to that of 667 but displaying different effector functions, and (ii) mice receiving no treatment but infected with a low viral inoculum reproducing the initial viral expansion observed in their infected/667 MAb-treated counterparts. Our data show that the reduction of FrCas(E) propagation is insufficient on its own to induce protective immunity and support a direct immunomodulatory action of the 667 MAb. Interestingly, they also point to sequential actions of the administered MAb. In a first step, viral propagation is exclusively controlled by 667 neutralizing activity, and in a second one, this action is complemented by FcgammaR-binding-dependent mechanisms, which most likely combine infected cell cytolysis and the modulation of the antiviral endogenous immune response. Such complementary effects of administered MAbs must be taken into consideration for the improvement of future antiviral MAb-based immunotherapies.

  18. pH-Dependent urea-induced unfolding of stem bromelain: unusual stability against urea at neutral pH.

    PubMed

    Ahmad, B; Rathar, G M; Varshney, A; Khan, R H

    2009-12-01

    Equilibrium unfolding of stem bromelain (SB) with urea as a denaturant has been monitored as a function of pH using circular dichroism and fluorescence emission spectroscopy. Urea-induced denaturation studies at pH 4.5 showed that SB unfolds through a two-state mechanism and yields DeltaG (free energy difference between the fully folded and unfolded forms) of approximately 5.0 kcal/mol and C(m) (midpoint of the unfolding transition) of approximately 6.5 M at 25 degrees C. Very high concentration of urea (9.5 M) provides unusual stability to the protein with no more structural loss and transition to a completely unfolded state.

  19. Matrix-assisted laser desorption/ionization mass spectrometry of neutral and acidic oligosaccharides with collision-induced dissociation.

    PubMed

    Mechref, Y; Baker, A G; Novotny, M V

    1998-12-15

    Using ribonuclease B and human alpha 1-acid glycoprotein (AGP) as model glycoproteins, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry with collision-induced dissociation (CID) is validated here as an effective tool for oligosaccharide sequencing. The spectra acquired for high-mannose and complex oligosaccharide structures show characteristic fragments resulting from cleavages of the glycosidic bonds and a few cross-ring cleavages. Esterification of the sialic acid residues is essential in stabilizing the acidic N-linked oligosaccharides. An important analytical feature observed in all acquired spectra is the occurrence of cleavages on the same antenna up to the branching point, as deduced from the absence of fragmentation due to the simultaneous cleavages on two or more antennas.

  20. Laser Induced Emission Spectroscopy of Cold and Isolated Neutral PAHs and PANH: Implications for the red rectangle emission

    NASA Astrophysics Data System (ADS)

    Bejaoui, Salma; Salama, Farid; Sciamma O'Brien, Ella

    2016-06-01

    Blue luminescence (BL) in the emission spectra of the red rectangle centered on the bright star HD44179 is recently reported by Vijh et al [1]. This results is consistent with the broad band polarization measurements obtained in 1980 by Schmidt et al. Both experimental and theoretical studies support that BL emission could be attributed the luminescence of Polycyclic Aromatic Hydrocarbon (PAH) excited with ultraviolet light from the center of the star [4 and reference therein]. The abundance on N to C in the interstellar medium suggest also that nitrogen substituted PAH (PANH) are likely abundant in the interstellar medium [3]. They exhibit similar features as PAHs and could contribute to the unidentified spectral bands. Comparing the BL to laboratory spectra obtained on similar environment is crucial for the identification of interstellar molecules. We present in this works the absorption and the laser induced emission spectra of several isolated and cold PAHs and PANHs. Laser induced emission was performed first to PAHs and PANHs isolated in Argon matrix at 10 K. Then, measurements are performed with the supersonic jet technique of the COSmIC laboratory facility at NASA Ames. We focus, here, on the emission spectra (fluorescence and (or) phosphorescence) of these molecules and we discuss their contributions to the blue luminescence emission in the Red Rectangle nebula.[1] Vijh,U.P., Witt. A.N. & Gordon,K.D, APJ, 606, L69 (2004)[2] Schmidt, G. D., Cohen, M. & Margon, B., ApJ, 239L.133S (1980)[3] Spitzer, L., Physical Processes in the Interstellar Medium (New York Wiley-Interscience) (1978)[4] Salama, F., Galazutdinov, G. A., Kre lowski, J., Allamandola, L. J., & Musaev, F. A. ApJ, 526,(1999)

  1. Specific sequences commonly found in the V3 domain of HIV-1 subtype C isolates affect the overall conformation of native Env and induce a neutralization-resistant phenotype independent of V1/V2 masking.

    PubMed

    Salomon, Aidy; Krachmarov, Chavdar; Lai, Zhong; Honnen, William; Zingman, Barry S; Sarlo, Julie; Gorny, Miroslaw K; Zolla-Pazner, Susan; Robinson, James E; Pinter, Abraham

    2014-01-01

    Primary HIV-1 isolates are relatively resistant to neutralization by antibodies commonly induced after infection or vaccination. This is generally attributed to masking of sensitive epitopes by the V1/V2 domain and/or glycans situated at various positions in Env. Here we identified a novel masking effect mediated by subtype C-specific V3 sequences that contributes to the V1/V2-independent and glycan-independent neutralization resistance of chimeric and primary Envs to antibodies directed against multiple neutralization domains. Positions at several conserved charged and hydrophobic sites in the V3 crown and stem were also shown to affect neutralization phenotype. These results indicated that substitutions typically present in subtype C and related V3 sequences influence the overall conformation of native Env in a way that occludes multiple neutralization targets located both within and outside of the V3 domain, and may reflect an alternative mechanism for neutralization resistance that is particularly active in subtype C and related isolates.

  2. The serum neutralizing antibody response in cattle to Fusobacterium necrophorum leukotoxoid and possible protection against experimentally induced hepatic abscesses.

    PubMed

    Saginala, S; Nagaraja, T G; Tan, Z L; Lechtenberg, K F; Chengappa, M M; Hine, P M

    1996-01-01

    The serum antileukotoxin antibody response and protection against subsequent experimental challenge with Fusobacterium necrophorum were investigated in 30 steers vaccinated with crude F. necrophorum leukotoxoid. Culture supernatant of F. necrophorum, strain 25, containing leukotoxoid was concentrated. The steers were assigned randomly to six groups (n = 5): PBS control with Stimulon adjuvant; vaccinated with concentrated supernatant diluted to provide 2.5, 5.0, 10.0, or 20.0 ml with the water-soluble Stimulon adjuvant; and 5.0 ml with the Ribi oil-emulsion adjuvant. The steers were injected subcutaneously on days 0 and 21. Blood samples were collected at weekly intervals to monitor serum antileukotoxin antibody titres. On day 42, all the steers were challenged intraportally with F. necrophorum culture. Three weeks later (day 63), the steers were killed and necropsied for examination of their livers and assessment of protection. Steers vaccinated with crude leukotoxoid tended to have higher antileukotoxin titres than the controls, but the difference was not significant. Also, the antibody titre did not appear to be dose-dependent. In the control group, 3 out of 5 steers developed liver abscesses. The incidence of liver abscesses in steers vaccinated with Stimulon adjuvant was not dose related; however, only 8 of the 25 vaccinated steers developed abscesses. None of the steers vaccinated with the 5.0 ml dose with Ribi had any abscesses. Evidence for a relationship between antileukotoxin antibody and protection was shown by the lower titre in those steers that developed abscesses compared to those that did not. It was concluded that antileukotoxin antibody titres probably provided some degree of protection against experimentally induced liver abscesses, but further dose-titration studies using Ribi or possibly another more effective adjuvant will be needed to confirm this.

  3. 'Candidatus Liberibacter americanus', associated with citrus huanglongbing (greening disease) in São Paulo State, Brazil.

    PubMed

    Teixeira, Diva do Carmo; Saillard, Colette; Eveillard, Sandrine; Danet, Jean Luc; da Costa, Paulo Inácio; Ayres, Antonio Juliano; Bové, Joseph

    2005-09-01

    , were found to have identical or almost identical sequences. In contrast, the intergenic regions of the SPS-HLB liberibacter, 'Ca. L. asiaticus' and 'Ca. L. africanus' had quite different sequences, with similarity between 66.0 and 79.5%. These results confirm that the SPS-HLB liberibacter is a novel species for which the name 'Candidatus Liberibacter americanus' is proposed. Like the African and the Asian liberibacters, the 'American' liberibacter is restricted to the sieve tubes of the citrus host. The liberibacter could also be detected by PCR amplification of the 16S rRNA gene in Diaphorina citri, the psyllid vector of 'Ca. L. asiaticus', suggesting that this psyllid is also a vector of 'Ca. L. americanus' in SPS. 'Ca. L. americanus' was detected in 216 of 218 symptomatic leaf samples from 47 farms in 35 municipalities, while 'Ca. L. asiaticus' was detected in only 4 of the 218 samples, indicating that 'Ca. L. americanus' is the major cause of HLB in SPS. PMID:16166678

  4. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus.

    PubMed

    Ferrari, Michele; Folli, Claudia; Pincolini, Elisa; McClintock, Timothy S; Rössle, Manfred; Berni, Rodolfo; Cianci, Michele

    2012-08-01

    Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H(1) and H(2) from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H(1) and H(2) with astaxanthin reproduced the bathochromic shift of 85-95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype-phenotype linkage. PMID:22869108

  5. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus

    PubMed Central

    Ferrari, Michele; Folli, Claudia; Pincolini, Elisa; McClintock, Timothy S.; Rössle, Manfred; Berni, Rodolfo; Cianci, Michele

    2012-01-01

    Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H1 and H2 from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H1 and H2 with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype–phenotype linkage. PMID:22869108

  6. Nutritional quality of the edible tissues of European lobster Homarus gammarus and American lobster Homarus americanus.

    PubMed

    Barrento, Sara; Marques, António; Teixeira, Bárbara; Vaz-Pires, Paulo; Nunes, Maria Leonor

    2009-05-13

    The clawed lobsters Homarus gammarus and Homarus americanus are high-priced and appreciated food items in southern Europe. From a nutritional point of view there is still limited information on the chemical composition of edible tissues (muscle, hepatopancreas, and gonads) of both species. Therefore, the aims of the present work were to study the proximate chemical composition, energy, fatty acid and amino acid profiles, and cholesterol content in each edible tissue of both species and to evaluate their nutritional quality. Differences were observed between tissues, sexes, and species. Muscle and gonads were rich in protein, whereas hepatopancreas had high fat, cholesterol, and energy contents. All edible tissues were valuable sources of essential amino acids. Contrary to the common belief that shellfish consumption should be reduced in a low-fat and -cholesterol diet, all edible tissues of clawed lobsters have a nutritious value perfectly compatible with nutritious and healthy diets. PMID:19334784

  7. [Polychaetes (Annelida: Polychaeta) epibiont on Spondylus americanus (Bivalvia: Spondylidae) from Mochima National Park, Venezuela].

    PubMed

    Liñero Arana, Ildefonso; Díaz Díaz, Oscar

    2006-09-01

    The polychaetes epibiontic on the mollusk Spondylus americanus Hermann, 1781 were extracted from mollusks hand-collected at a depth of 10-30 m in Mochima National Park, Venezuela (10 degrees 21'00" N-63 degrees 23'36" W), using scuba diving gear. Forty-three polychaete species were identified on the 32 bivalve specimens analyzed. The Serpulidae included 17 especies, Eunicidae six and Terebellidae four species. The most abundant species were Hydroides dirampha Mörch, 1863, Pileolaria militaris Claparède, 1868 (Serpulidae), and Notaulax nudicollis Krøyer, 1856 (Sabellidae). Their geographic affinitie were: 51.3% Atlantic, 28.2% widely distributed, 17.9% Amphiamericans, and 2.6% have a disjunct distribution.

  8. Sex steroid and prolactin profiles in male American black bears (Ursus americanus) during denning.

    PubMed

    Tsubota, T; Garshelis, D L; Nelson, R A; Bahr, J M

    1999-01-01

    Serum sex steroid and prolactin profiles were examined in the male American black bear, Ursus americanus during denning. Sera collected in December and the following March from 8 denning male black bears in Minnesota, U.S.A. were assayed for testosterone, estradiol-17 beta and prolactin. Eight bears were confirmed to be the denning mode based on a serum urea to creatinine ratio less than 10. Serum testosterone concentrations tended to increase from December to the subsequent March whereas serum estradiol-17 beta concentrations tended to decrease during this period. There were few changes in serum prolactin concentrations between December and March. These findings suggest that spermatogenesis and testicular steroidogenesis initiated during denning may be influenced by changes in serum sex steroid concentrations in the American black bear. PMID:10027172

  9. Fatal disseminated blastomycosis in a free-ranging American black bear (Ursus americanus).

    PubMed

    Dykstra, Jaclyn A; Rogers, Lynn L; Mansfield, Susan A; Wünschmann, Arno

    2012-11-01

    An aged, free-ranging, female, radio-collared American black bear (Ursus americanus) died after an approximately 5 month long period of weight loss. Gross necropsy findings included severe diffuse pyogranulomatous bronchopneumonia, marked granulomatous lymphadenitis of tracheobronchial lymph nodes and multiple intra-abdominal lymph nodes, chronic focal jejunal ulceration, and widespread alopecia. Histopathologic examination revealed abundant fungal organisms morphologically compatible with Blastomyces sp. within pyogranulomatous inflammatory lesions in the lungs, multiple lymph nodes, liver, kidneys, jejunum, and right adrenal gland. In addition, the haircoat had a mild infestation of chewing lice (Trichodectes pinguis euarctidos), and large numbers of rhabditid nematodes consistent with Pelodera sp. were histologically observed within hair follicles. PMID:23012379

  10. Sarcoptic mange and Pelodera dermatitis in an American black bear (Ursus americanus).

    PubMed

    Fitzgerald, Scott D; Cooley, Thomas M; Cosgrove, Melinda K

    2008-06-01

    An adult female free-ranging American black bear (Ursus americanus) was presented in poor body condition, with advanced skin disease. Skin changes included hair loss, lichenification, crusting, and focal erosions. Skin scrapings and histopathology identified two distinct parasitic conditions that were contributing to this animal's dermatitis. Large numbers of larvae, nymphs, and adults of Sarcoptes scabiei were present in the superficial epidermis, and nematodes consistent with Pelodera strongyloides were abundant within the hair follicles. This appears to be the first reported case of Pelodera dermatitis in a bear species, adding a new differential agent to the list for dermatitis in bears. The sarcoptic mange and poor body condition of this bear may have been contributing factors to the development of the opportunistic Pelodera infestation. PMID:18634219

  11. Laryngeal squamous cell carcinoma in a North American black bear (Ursus americanus).

    PubMed

    Rotstein, David S; Govett, Pamela; Wolfe, Barbara

    2005-09-01

    A 10-yr-old female black bear (Ursus americanus) at the North Carolina Zoological Park presented with a 2-wk history of intermittent coughing and stertor. The animal was anesthetized for examination, and at intubation, a large mass associated with the tonsils and larynx was observed obstructing the airway. Cardiopulmonary collapse occurred during the procedure, and efforts at resuscitation were ineffective. At necropsy, an 8 cm times 6 cm times 5 cm mass was present in the larynx, infiltrating the epiglottis and obstructing the airway. Regional lymph nodes were mildly enlarged and contained tan inspissated substance. Histologically, the neoplasm was composed of nests of keratinizing squamous epithelial cells with evidence of lymphatic invasion and metastases to regional lymph nodes. PMID:17312782

  12. A description of a new "Amoebozoan" isolated from the American lobster, Homarus americanus.

    PubMed

    Cole, Jeffrey; Anderson, O Roger; Tekle, Yonas I; Grant, Jessica; Kat, Laura A; Nerad, Thomas

    2010-01-01

    Our knowledge of the diversity of amoeboid protists is rapidly expanding as new and old habitats are more fully explored. In 2003, while investigating the cause of an amoeboid disease afflicting lobsters on the East Coast, samples were examined for the presence of amoebae from the carapace washings of the American lobster, Homarus americanus. During this survey a unique community of gymnamoebae was discovered. Among the new taxa discovered was a small Thecamoeba-like organism with a single posteriorly directed pseudopodium. Although resembling Parvamoeba rugata, this amoeba displayed distinctive morphology from that isolate or any other amoebozoan. Phylogenetic analysis shows this amoeba is distantly related to the Thecamoebidae. In this paper we describe the unique morphology of a second species of Parvamoeba and discuss its phylogenetic position with respect to the "Amoebozoa."

  13. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus.

    PubMed

    Ferrari, Michele; Folli, Claudia; Pincolini, Elisa; McClintock, Timothy S; Rössle, Manfred; Berni, Rodolfo; Cianci, Michele

    2012-08-01

    Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H(1) and H(2) from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H(1) and H(2) with astaxanthin reproduced the bathochromic shift of 85-95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype-phenotype linkage.

  14. Structure of a two-CAP-domain protein from the human hookworm parasite Necator americanus

    SciTech Connect

    Asojo, Oluwatoyin A.

    2011-05-01

    The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite N. americanus refined to a resolution limit of 2.2 Å is presented. Major proteins secreted by the infective larval stage hookworms upon host entry include Ancylostoma secreted proteins (ASPs), which are characterized by one or two CAP (cysteine-rich secretory protein/antigen 5/pathogenesis related-1) domains. The CAP domain has been reported in diverse phylogenetically unrelated proteins, but has no confirmed function. The first structure of a two-CAP-domain protein, Na-ASP-1, from the major human hookworm parasite Necator americanus was refined to a resolution limit of 2.2 Å. The structure was solved by molecular replacement (MR) using Na-ASP-2, a one-CAP-domain ASP, as the search model. The correct MR solution could only be obtained by truncating the polyalanine model of Na-ASP-2 and removing several loops. The structure reveals two CAP domains linked by an extended loop. Overall, the carboxyl-terminal CAP domain is more similar to Na-ASP-2 than to the amino-terminal CAP domain. A large central cavity extends from the amino-terminal CAP domain to the carboxyl-terminal CAP domain, encompassing the putative CAP-binding cavity. The putative CAP-binding cavity is a characteristic cavity in the carboxyl-terminal CAP domain that contains a His and Glu pair. These residues are conserved in all single-CAP-domain proteins, but are absent in the amino-terminal CAP domain. The conserved His residues are oriented such that they appear to be capable of directly coordinating a zinc ion as observed for CAP proteins from reptile venoms. This first structure of a two-CAP-domain ASP can serve as a template for homology modeling of other two-CAP-domain proteins.

  15. Functional morphology of gill ventilation of the goosefish, Lophius americanus (Lophiiformes: Lophiidae).

    PubMed

    Farina, Stacy C; Bemis, William E

    2016-06-01

    The goosefish, Lophius americanus, is a dorso-ventrally compressed marine fish that spends most of its life sitting on the substrate waiting to ambush prey. Species in the genus Lophius have some of the slowest ventilatory cycles recorded in fishes, with a typical cycle lasting more than 90s. They have a large gill chamber, supported by long branchiostegal rays and ending in a siphon-like gill opening positioned underneath and behind the base of the pectoral fin. Our goals were to characterize the kinematics of gill ventilation in L. americanus relative to those of more typical ray-finned fishes, address previous assertions about ventilation in this genus, and describe the anatomy of the gill opening. We found that phase 1 of ventilation (during which both the buccal and gill chamber are expanding) is greatly increased in duration relative to that of typical ray-finned fishes (ranging from 62 to 127s), and during this phase, the branchiostegal rays are slowly expanding. This slow expansion is almost visually imperceptible, especially from a dorsal view. Despite this unusually long phase 1, the pattern of skeletal movements follows that of a typical actinopterygian, refuting previous assertions that Lophius does not use its jaws, suspensorium, and operculum during ventilation. When individuals were disturbed from the sediment, they tended to breathe more rapidly by decreasing the duration of phase 1 (to 18-30s). Dissections of the gill opening revealed a previously undocumented dorsal extension of the adductor hyohyoideus muscle, which passes from between the branchiostegal rays, through the ventro-medial wall of the gill opening, and to the dorsal midline of the body. This morphology of the adductor hyohyoideus shares similarities with that of many Tetraodontiformes, and we suggest that it may be a synapomorphy for Lophiiformes+Tetraodontiformes. The specialized anatomy and function of the gill chamber of Lophius represents extreme modifications that provide

  16. Vaccines prepared from chimeras of foot-and-mouth disease virus (FMDV) induce neutralizing antibodies and protective immunity to multiple serotypes of FMDV.

    PubMed

    Rieder, E; Baxt, B; Lubroth, J; Mason, P W

    1994-11-01

    The G-H loop of VP1 (residues 132 to 159) of foot-and-mouth disease virus (FMDV) is a prominent feature on the virion surface and has an important role in vaccine efficacy, generation of antigenic variants, and cell binding. Using an infectious cDNA of FMDV, we have constructed serotype A viruses in which the G-H loop has been substituted with the homologous sequences from serotype O or C. These chimeric viruses replicated to high titer and displayed plaque morphologies similar to those of wild-type viruses, demonstrating that the functions provided by the loop can be readily exchanged between serotypes. Monoclonal antibody analyses showed that epitopes contained within the loop were transferred to the chimeras and that epitopes encoded by the type A backbone were maintained. Chemically inactivated vaccines prepared from chimeric viruses induced antibodies in guinea pigs that neutralized both type A and either type O or type C viruses. Swine inoculated with the A/C chimera vaccine also produced cross-reactive antibodies, were protected from challenge with the type A virus, and partially protected against challenge with type C. These studies emphasize the importance of epitopes outside of the G-H loop in protective immunity in swine, which is a natural host of FMDV. PMID:7523697

  17. Fatty acid neutral losses observed in tandem mass spectrometry with collision-induced dissociation allows regiochemical assignment of sulfoquinovosyl-diacylglycerols.

    PubMed

    Zianni, Rosalia; Bianco, Giuliana; Lelario, Filomena; Losito, Ilario; Palmisano, Francesco; Cataldi, Tommaso R I

    2013-02-01

    A full characterization of sulfoquinovosyldiacylglycerols (SQDGs) in the lipid extract of spinach leaves has been achieved using liquid chromatography/electrospray ionization-linear quadrupole ion trap mass spectrometry (MS). Low-energy collision-induced dissociation tandem MS (MS/MS) of the deprotonated species [M - H](-) was exploited for a detailed study of sulfolipid fragmentation. Losses of neutral fatty acids from the acyl side chains (i.e. [M - H - RCOOH](-)) were found to prevail over ketene losses ([M - H - R'CHCO](-)) or carboxylates of long-chain fatty acids ([RCOO](-)), as expected for gas-phase acidity of SQDG ions. A new concerted mechanism for RCOOH elimination, based on a charge-remote fragmentation, is proposed. The preferential loss of a fatty acids molecule from the sn-1 position (i.e. [M - H - R(1)COOH](-)) of the glycerol backbone, most likely due to kinetic control of the gas-phase fragmentation process, was exploited for the regiochemical assignment of the investigated sulfolipids. As a result, 24 SQDGs were detected and identified in the lipid extract of spinach leaves, their number and variety being unprecedented in the field of plant sulfolipids. Moreover, the prevailing presence of a palmitic acyl chain (16:0) on the glycerol sn-2 position of spinach SQDGs suggests a prokaryotic or chloroplastic path as the main route for their biosynthesis.

  18. Ammonia-containing industrial effluents, lethal to rainbow trout, induce vacuolisation and Neutral Red uptake in the rainbow trout gill cell line, RTgill-W1.

    PubMed

    Dayeh, Vivian R; Schirmer, Kristin; Bols, Niels C

    2009-02-01

    Nine samples of whole effluent from the operation of an industrial plant over the course of one year, were tested on rainbow trout for lethality and on the rainbow trout gill cell line, RTgill-W1, for metabolic activity, plasma membrane integrity, and lysosomal activity, as measured by using the alamar Blue (AB), 5-carboxyfluorescein diacetate acetoxymethyl (CFDA-AM), and neutral red (NR) assays, respectively. None of the nine samples caused a loss of plasma membrane integrity, and only two caused a transitory decline in metabolism. Three samples caused massive vacuolisation in RTgill-W1 cells, which was accompanied by increased uptake of NR, and only these three samples were lethal to the rainbow trout. The addition of ammonia to RTgill-W1 cultures also induced vacuolisation and NR uptake, with little change in plasma membrane integrity or metabolism. Subsequently, the effluent source was identified as a nitrogen product producer, and variable levels of ammonia were found in the nine samples. Three of the four samples with the highest non-ionised ammonia levels were those which were toxic to rainbow trout and which caused vacuoles in RTgill-W1 cells. The close correlation between rainbow trout-killing and RTgill-W1 vacuolisation by the effluents, suggests that vacuolisation of RTgill-W1 cells could be used to indicate effluents which would be toxic to rainbow trout as a result of their ammonia content.

  19. Vaccine-induced virus-neutralizing antibodies and cytotoxic T cells do not protect macaques from experimental infection with simian immunodeficiency virus SIVmac32H (J5).

    PubMed Central

    Hulskotte, E G; Geretti, A M; Siebelink, K H; van Amerongen, G; Cranage, M P; Rud, E W; Norley, S G; de Vries, P; Osterhaus, A D

    1995-01-01

    To gain further insight into the ability of subunit vaccines to protect monkeys from experimental infection with simian immunodeficiency virus (SIV), two groups of cynomolgus macaques were immunized with either recombinant SIVmac32H-derived envelope glycoproteins (Env) incorporated into immune-stimulating complexes (iscoms) (group A) or with these SIV Env iscoms in combination with p27gag iscoms and three Nef lipopeptides (group B). Four monkeys immunized with recombinant feline immunodeficiency virus Env iscoms served as controls (group C). Animals were immunized intramuscularly at weeks 0, 4, 10, and 16. Two weeks after the last immunization, monkeys were challenged intravenously with 50 monkey 50% infectious doses of virus derived from the J5 molecular clone of SIVmac32H propagated in monkey peripheral blood mononuclear cells. High titers of SIV-neutralizing antibodies were induced in the monkeys of groups A and B. In addition, p27gag-specific antibodies were detected in the monkeys of group B. Vaccine-induced cytotoxic-T-lymphocyte precursors against Env, Gag, and Nef were detected on the day of challenge in the monkeys of group B. Env-specific cytotoxic-T-lymphocyte precursors were detected in one monkey from group A. In spite of the observed antibody and T-cell responses, none of the monkeys was protected from experimental infection. In addition, longitudinal determination of cell-associated virus loads at weeks 2, 4, 6, 9, and 12 postchallenge revealed no significant differences between vaccinated and control monkeys. These findings illustrate the need to clarify the roles of the different arms of the immune system in conferring protection against primate lentivirus infections. PMID:7666529

  20. Investigating the mechanism for maintaining eucalcemia despite immobility and anuria in the hibernating American black bear (Ursus americanus).

    PubMed

    Seger, Rita L; Cross, Randal A; Rosen, Clifford J; Causey, Robert C; Gundberg, Caren M; Carpenter, Thomas O; Chen, Tai C; Halteman, William A; Holick, Michael F; Jakubas, Walter J; Keisler, Duane H; Seger, Richard M; Servello, Frederick A

    2011-12-01

    Ursine hibernation uniquely combines prolonged skeletal unloading, anuria, pregnancy, lactation, protein recycling, and lipolysis. This study presents a radiographic and biochemical picture of bone metabolism in free-ranging, female American black bears (Ursus americanus) that were active (spring bears and autumn bears) or hibernating (hibernating bears). Hibernating bears included lactating and non-lactating individuals. We measured serum calcium, albumin, inorganic phosphate, creatinine, bone specific alkaline phosphatase (BSALP), CTX, parathyroid hormone, insulin-like growth factor-I (IGF-l), leptin, 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D] and sclerostin from 35 to 50 tranquilized hibernating bears and 14 to 35 tranquilized spring bears. We compared metacarpal cortical indices (MCI), measured by digital X-ray radiogrammetry, from 60 hunter-killed autumn bears and 79 tranquilized, hibernating bears. MCI was greater in autumn than winter in younger bears, but showed no seasonal difference in older bears. During hibernation eucalcemia was maintained, BSALP was suppressed, and CTX was in the range expected for anuria. During hibernation 1,25(OH)(2)D was produced despite anuria. 1,25(OH)(2)D and IGF-I were less in hibernating than spring bears. In a quarter of hibernating bears, sclerostin was elevated. Leptin was greater in hibernating than spring bears. In hibernating bears, leptin correlated positively with BSALP in non-lactating bears and with CTX in lactating bears. Taken together the biochemical and radiographic findings indicate that during hibernation, bone turnover was persistent, balanced, and suppressed; bone resorption was lower than expected for an unloaded skeleton; and there was no unloading-induced bone loss. The skeleton appears to perceive that it was loaded when it was actually unloaded during hibernation. However, at the level of sclerostin, the skeleton recognized that it was unloaded. During hibernation leptin

  1. Photodetachment process for beam neutralization

    DOEpatents

    Fink, J.H.; Frank, A.M.

    1979-02-20

    A process for neutralization of accelerated ions employing photo-induced charge detachment is disclosed. The process involves directing a laser beam across the path of a negative ion beam such as to effect photodetachment of electrons from the beam ions. The frequency of the laser beam employed is selected to provide the maximum cross-section for the photodetachment process. 2 figs.

  2. Photodetachment process for beam neutralization

    DOEpatents

    Fink, Joel H. [Livermore, CA; Frank, Alan M. [Livermore, CA

    1979-02-20

    A process for neutralization of accelerated ions employing photo-induced charge detachment. The process involves directing a laser beam across the path of a negative ion beam such as to effect photodetachment of electrons from the beam ions. The frequency of the laser beam employed is selected to provide the maximum cross-section for the photodetachment process.

  3. A transcriptomic analysis of American lobster (Homarus americanus) immune response during infection with the bumper car parasite Anophryoides haemophila.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Greenwood, Spencer J

    2013-06-01

    Anophryoides haemophila is an important protistan parasite of American lobster, Homarus americanus, as it has been found to infect lobsters in the wild as well as causing major losses of lobsters maintained in commercial holding facilities. Expression of over 14,500 H. americanus hepatopancreatic genes were monitored during an A. haemophila infection challenge in order to elucidate molecular mechanisms involved in the lobster immune response. One hundred and forty-five genes were found to be differentially expressed during infection. For many genes, this study is the first to link their expression to an immune response to a known lobster pathogen. Several of the genes have previously been linked to crustacean or invertebrate immune response including: several anti-lipopolysaccharide factor isoforms (ALFHa), acute phase serum amyloid protein A (SAA), a serine protease inhibitor, a toll-like receptor, several haemocyanin subunits, phagocyte signaling-impaired protein, vitelline membrane outer layer protein-1, trypsin, and a C-type lectin receptor. Microarray results were verified using RT-qPCR and agreement was good between the two methods. The expression of six ALFHa isoforms was monitored via microarray where ALFHa-1, ALFHa-2, ALFHa-4 and ALFHa-6 were differentially expressed while ALFHa-3 and ALFHa7 were not. RT-qPCR analysis confirmed that ALFHa-1, ALFHA-2 and ALFHa-4 expression increased during infection with a peak at 5-7weeks for ALFHa-1 and 10weeks for ALFHa-2 and ALFHa-4. This suggests that different ALFHa isoforms are temporally expressed during A. haemophila infection. Importantly, these results provide evidence that different ALFHa isoforms have more significant roles in responding to A. haemophila infection. Significant increases in SAA gene expression were also found, corroborating previous findings of increased SAA expression during Aerococcus viridans infections; highlighting the importance of SAA as a marker of H. americanus immune activation and

  4. Anti-lipopolysaccharide factors in the American lobster Homarus americanus: Molecular characterization and transcriptional response to Vibrio fluvialis challenge

    PubMed Central

    Beale, K.M.; Towle, D.W.; Jayasundara, N.; Smith, C.M.; Shields, J.D.; Small, H.J.; Greenwood, S.J.

    2008-01-01

    Two partial mRNA sequences predicted to encode anti-lipopolysaccharide factors (ALFs) were identified among expressed sequence tags generated from the American lobster Homarus americanus and complete cDNA sequences were obtained from library clones. Comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. Both protein sequences, designated ALFHa-1 and ALFHa-2, contained an N-terminal signal peptide and two half-cysteines participating in a disulfide bridge, features conserved in other ALFs. Predicted secondary structures were similar to that described for the ALF from the horseshoe crab Limulus polyphemus. As part of an exploratory study of immunity in H. americanus, lobsters were injected with the bacterium Vibrio fluvialis and gill, hematopoietic, and hepatopancreas tissues were sampled for analysis of gene expression of ALFHa-1 and ALFHa-2 by quantitative PCR. The relative abundance of ALFHa-2 mRNA was not significantly affected by Vibrio injection in any of the three tissues tested. In contrast, ALFHa-1 mRNA levels in gills were increased by the treatment some 17-fold. Our results support a molecularly specific regulation of antimicrobial proteins in response to bacterial infection in H. americanus. PMID:19956341

  5. Epidemiological evidence for a differential effect of hookworm species, Ancylostoma duodenale or Necator americanus, on iron status of children.

    PubMed

    Albonico, M; Stoltzfus, R J; Savioli, L; Tielsch, J M; Chwaya, H M; Ercole, E; Cancrini, G

    1998-06-01

    Hookworms infect 1.3 billion people annually. Iron-deficiency anemia caused or exacerbated by intestinal blood loss is the major feature of hookworm infection, with such loss caused by the feeding of hookworms upon the intestinal mucosa. The hookworms Ancylostoma duodenale and Necator americanus cause major gastrointestinal blood loss. While relatively greater blood loss has been reported in clinical studies due to infection with A. duodenale, there has been no evidence that endemic A. duodenale infection has a greater impact than N. americanus infection upon the iron status of populations. The authors compared the degree of anemia and iron deficiency associated with these 2 hookworm species at the individual and community levels using a sample of 525 school children in grades 1-4 in Pemba Island, Tanzania, and controlling for infection intensities and other child characteristics through multiple regression. In the 492 children with hookworm-positive fecal cultures, hemoglobin and ferritin concentrations decreased with increasing proportions of A. duodenale. Among children with only N. americanus larvae, the prevalence of anemia was 60.5% and the prevalence of ferritin under 12 mcg/l was 33.1%. In children with 50% or higher proportions of A. duodenale larvae, the respective prevalences were 80.6% and 58.9%. Children from schools with high prevalences of A. duodenale infection had significantly worse iron deficiency and anemia than did children from low prevalence schools.

  6. First report of Taenia arctos (Cestoda: Taeniidae) from grizzly (Ursus arctos horribilis) and black bears (Ursus americanus) in North America.

    PubMed

    Catalano, Stefano; Lejeune, Manigandan; Verocai, Guilherme G; Duignan, Pádraig J

    2014-04-01

    The cestode Taenia arctos was found at necropsy in the small intestine of a grizzly (Ursus arctos horribilis) and a black bear (Ursus americanus) from Kananaskis Country in southwestern Alberta, Canada. The autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial DNA cytochrome c oxidase subunit 1 gene confirmed their identity as T. arctos. This is the first report of T. arctos from definitive hosts in North America. Its detection in Canadian grizzly and black bears further supports the Holarctic distribution of this tapeworm species and its specificity for ursids as final hosts. Previously, T. arctos was unambiguously described at its adult stage in brown bears (Ursus arctos arctos) from Finland, and as larval stages in Eurasian elk (Alces alces) from Finland and moose (Alces americanus) from Alaska, USA. Given the morphological similarity between T. arctos and other Taenia species, the present study underlines the potential for misidentification of tapeworm taxa in previous parasitological reports from bears and moose across North America. The biogeographical history of both definitive and intermediate hosts in the Holarctic suggests an ancient interaction between U. arctos, Alces spp., and T. arctos, and a relatively recent host-switching event in U. americanus.

  7. First report of Taenia arctos (Cestoda: Taeniidae) from grizzly (Ursus arctos horribilis) and black bears (Ursus americanus) in North America.

    PubMed

    Catalano, Stefano; Lejeune, Manigandan; Verocai, Guilherme G; Duignan, Pádraig J

    2014-04-01

    The cestode Taenia arctos was found at necropsy in the small intestine of a grizzly (Ursus arctos horribilis) and a black bear (Ursus americanus) from Kananaskis Country in southwestern Alberta, Canada. The autolysis of the tapeworm specimens precluded detailed morphological characterization of the parasites but molecular analysis based on mitochondrial DNA cytochrome c oxidase subunit 1 gene confirmed their identity as T. arctos. This is the first report of T. arctos from definitive hosts in North America. Its detection in Canadian grizzly and black bears further supports the Holarctic distribution of this tapeworm species and its specificity for ursids as final hosts. Previously, T. arctos was unambiguously described at its adult stage in brown bears (Ursus arctos arctos) from Finland, and as larval stages in Eurasian elk (Alces alces) from Finland and moose (Alces americanus) from Alaska, USA. Given the morphological similarity between T. arctos and other Taenia species, the present study underlines the potential for misidentification of tapeworm taxa in previous parasitological reports from bears and moose across North America. The biogeographical history of both definitive and intermediate hosts in the Holarctic suggests an ancient interaction between U. arctos, Alces spp., and T. arctos, and a relatively recent host-switching event in U. americanus. PMID:24382413

  8. Prompt non-resonant neutral beam-ion loss induced by Alfvén eigenmodes in the DIII-D tokamak

    NASA Astrophysics Data System (ADS)

    Chen, X.; Heidbrink, W. W.; Kramer, G. J.; Van Zeeland, M. A.; Austin, M. E.; Fisher, R. K.; Nazikian, R.; Pace, D. C.; Petty, C. C.

    2013-12-01

    Prompt neutral beam-ion loss due to non-resonant scattering caused by toroidicity-induced and reversed shear Alfvén eigenmodes (TAE/RSAEs) have been observed in DIII-D. The coherent losses are of full-energy beam ions born on unperturbed trapped orbits that would carry them close to a fast-ion loss detector (FILD) within one poloidal transit. However, in the presence of AEs, the particles are expelled from the plasma before completing their first poloidal orbits. The loss signals on FILD emerge within 100 µs after the beam switch-on (which is the time scale of a single poloidal transit) and oscillate at mode frequencies. Time-resolved loss measurements show a linear dependence on the AE fluctuation amplitude and a radial ‘kick’ of ˜10 cm by an n = 2 RSAE at δB/B ⩽ 1 × 10-3 can be directly inferred from the measurements. Full-orbit modelling of the fast-ion displacement caused by the AEs is in good quantitative agreement with the measurements. Direct interactions of the mode and the beam-ion orbit can account for a large fraction of fast-ion losses observed in such DIII-D discharges. The first orbit non-resonant loss mechanism may also contribute to enhanced localized losses in ITER and future reactors. A new diagnostic method of the radial displacement is inspired by these findings and can be used to study the interaction between fast ions and various MHD modes as well as three-dimensional fields.

  9. Microspheres containing neutralizing antibodies to tumor necrosis factor-alpha and interleukin-1 beta protect rats from Staphylococcus aureus-induced peritonitis.

    PubMed

    D'Souza, M; Oettinger, C W; Milton, G V

    2000-10-01

    Previous studies using microencapsulated neutralizing antibodies (NA) to tumor necrosis factor (TNF) and interleukin-1 (IL-1) in combination with gentamicin have demonstrated improved survival in a peritonitis model of gram-negative septic shock. Microencapsulation has been shown to improve the effectiveness of NA by delivering them intracellularly, taking advantage of the natural phagocytic activity of the macrophage. It is the purpose of this study to see if microencapsulated NA to TNF and IL-1 in combination with vancomycin can improve survival compared with NA in solution in Staphlococcus aureus-induced septic shock. Groups of 10 rats received the following treatments: (1) S. aureus plus no treatment, (2) S. aureus plus blank microspheres, (3) S. aureus plus vancomycin, (4) S. aureus plus a microsphere form of NA and vancomycin, (5) S. aureus plus a solution form of NA and vancomycin, (6) S. aureus plus a microsphere form of NA, and (7) S. aureus plus a solution form of NA. Survival was monitored for 5 days, and plasma TNF and IL-1 levels were measured for 48 h after S. aureus administration. All (100%) animals that received the microsphere form of NA plus vancomycin, 20%-70% of the animals that received the microsphere form of NA alone, and 20% of the animals that received antibiotics alone survived for 5 days or more. None of the animals in the no treatment group or blank microsphere treatment group and only 10% of the animals in the solution form of NA plus or minus vancomycin group survived for more than 5 days. Plasma TNF and IL-1 levels were significantly increased after S. aureus treatment. Simultaneous and delayed treatment with the microsphere form of NA plus or minus vancomycin significantly reduced TNF and IL-1 levels, and the solution form of NA significantly reduced only TNF levels after immediate treatment. The survival rate was higher in animals with lower TNF levels and IL-1 levels. The results demonstrate that the microsphere form of cytokine

  10. Design of an Escherichia coli Expressed HIV-1 gp120 Fragment Immunogen That Binds to b12 and Induces Broad and Potent Neutralizing Antibodies

    PubMed Central

    Bhattacharyya, Sanchari; Singh, Pranveer; Rathore, Ujjwal; Purwar, Mansi; Wagner, Denise; Arendt, Heather; DeStefano, Joanne; LaBranche, Celia C.; Montefiori, David C.; Phogat, Sanjay; Varadarajan, Raghavan

    2013-01-01

    b12, one of the few broadly neutralizing antibodies against HIV-1, binds to the CD4 binding site (CD4bs) on the gp120 subunit of HIV-1 Env. Two small fragments of HIV-1 gp120, b121a and b122a, which display about 70% of the b12 epitope and include solubility-enhancing mutations, were designed. Bacterially expressed b121a/b122a were partially folded and could bind b12 but not the CD4bs-directed non-neutralizing antibody b6. Sera from rabbits primed with b121a or b122a protein fragments and boosted with full-length gp120 showed broad neutralizing activity in a TZM-bl assay against a 16-virus panel that included nine Tier 2 and 3 viruses as well as in a five-virus panel previously designed to screen for broad neutralization. Using a mean IC50 cut-off of 50, sera from control rabbits immunized with gp120 alone neutralized only one virus of the 14 non-Tier 1 viruses tested (7%), whereas sera from b121a- and b122a-immunized rabbits neutralized seven (50%) and twelve (86%) viruses, respectively. Serum depletion studies confirmed that neutralization was gp120-directed and that sera from animals immunized with gp120 contained lower amounts of CD4bs-directed antibodies than corresponding sera from animals immunized with b121a/b122a. Competition binding assays with b12 also showed that b121a/2a sera contained significantly higher amounts of antibodies directed toward the CD4 binding site than the gp120 sera. The data demonstrate that it is possible to elicit broadly neutralizing sera against HIV-1 in small animals. PMID:23430741

  11. Meteorological effects on the biting activity of Leptoconops americanus(Diptera: Ceratopogonidae).

    PubMed

    Strickman, D; Wirtz, R; Lawyer, P; Glick, J; Stockwell, S; Perich, M

    1995-03-01

    Collections of biting Leptoconops americanus were made at half-hour intervals throughout the daylight hours on Stansbury Island, UT, during 9 days in May, 1993. The most favorable conditions for biting (> or = 90 bites on the ears in 15 min) included temperatures higher than 15 degrees C, minimum wind (< 5 kph), minimum cloud cover, maximum sun, and no rain. Temperatures below 10 degrees C or the presence of rain prevented almost all biting. Higher winds and cloudiness decreased biting activity, but did not eliminate it if other conditions were favorable. Although not statistically significant, there was some suggestion from the data that higher temperatures (> 25 degrees C) reduced biting. The flies did not appear to be more numerous at any particular part of the day; the biting rate simply followed meteorological conditions at the time. Ambient light varied between 1 and 10,000 foot candles during the study, with high biting rates (76 and 99 bites per 15 min) observed at levels as low as 80-100 foot candles.

  12. Serosurvey for selected pathogens in free-ranging American black bears (Ursus americanus) in Maryland, USA.

    PubMed

    Bronson, Ellen; Spiker, Harry; Driscoll, Cindy P

    2014-10-01

    American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Maryland counties and tested them for exposure to infectious, including zoonotic, pathogens. A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower. Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsii, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis. Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied. Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health.

  13. Seasonal variation in American black bear Ursus americanus activity patterns: Quantification via remote photography

    USGS Publications Warehouse

    Bridges, A.S.; Vaughan, M.R.; Klenzendorf, S.

    2004-01-01

    Activity pattern plasticity may serve as an evolutionary adaptation to optimize fitness in an inconstant environment, however, quantifying patterns and demonstrating variation can be problematic. For American black bears Ursus americanus, wariness and habitat inaccessibility further complicate quantification. Radio telemetry has been the primary technique used to examine activity, however, interpretation error and limitation on numbers of animals available to monitor prevent extrapolation to unmarked or untransmittered members of the population. We used remote cameras to quantify black bear activity patterns and examined differences by season, sex and reproductive class in the Alleghany Mountains of western Virginia, USA. We used 1,533 pictures of black bears taken during 1998-2002 for our analyses. Black bears generally were diurnal in summer and nocturnal in autumn with a vespertine activity peak during both seasons. Bear-hound training seasons occurred during September and may offer explanation for the observed shift towards nocturnal behaviour. We found no substantial differences in activity patterns between sex and reproductive classes. Use of remote cameras allowed us to efficiently sample larger numbers of individual animals and likely offered a better approximation of population-level activity patterns than individual-level, telemetry-based methodologies.

  14. Social network analysis of mating patterns in American black bears (Ursus americanus).

    PubMed

    Moore, Jennifer A; Xu, Ran; Frank, Kenneth; Draheim, Hope; Scribner, Kim T

    2015-08-01

    Nonrandom mating can structure populations and has important implications for population-level processes. Investigating how and why mating deviates from random is important for understanding evolutionary processes as well as informing conservation and management. Prior to the implementation of parentage analyses, understanding mating patterns in solitary, elusive species like bears was virtually impossible. Here, we capitalize on a long-term genetic data set collected from black bears (Ursus americanus) (N = 2422) in the Northern Lower Peninsula (NLP) of Michigan, USA. We identified mated pairs using parentage analysis and applied logistic regression (selection) models that controlled for features of the social network, to quantify the effects of individual characteristics, and spatial and population demographic factors on mating dynamics. Logistic regression models revealed that black bear mating was associated with spatial proximity of mates, male age, the time a pair had coexisted, local population density and relatedness. Mated pairs were more likely to contain older males. On average, bears tended to mate with nearby individuals to whom they were related, which does not support the existence of kin recognition in black bears. Pairwise relatedness was especially high for mated pairs containing young males. Restricted dispersal and high male turnover from intensive harvest mortality of NLP black bears are probably the underlying factors associated with younger male bears mating more often with female relatives. Our findings illustrate how harvest has the potential to disrupt the social structure of game species, which warrants further attention for conservation and management. PMID:26113220

  15. Aroma components of cooked tail meat of American lobster (Homarus americanus).

    PubMed

    Lee, G H; Suriyaphan, O; Cadwallader, K R

    2001-09-01

    Key aroma components of cooked tail meat of American lobster (Homarus americanus) were studied by gas chromatography-olfactometry (GCO) techniques. Components of low and intermediate volatility were evaluated by aroma extract dilution analysis of solvent extracts prepared by direct solvent extraction-high vacuum distillation and vacuum steam distillation-solvent extraction, whereas headspace volatile components were assessed by GCO of decreasing headspace (static and dynamic modes) samples. Forty-seven odorants were detected by all techniques. 3-Methylbutanal (chocolate, malty), 2,3-butanedione (buttery), 3-(methylthio)propanal (cooked potato), 1-octen-3-one (mushroom), 2-acetyl-1-pyrroline (popcorn), and (E,Z)-2,6-nonadienal (cucumber), were identified as predominant odorants by all four isolation methods. The highly volatile compounds methanethiol (rotten, sulfurous) and dimethyl sulfide (canned corn) were detected by headspace methods only. These eight odorants along with three unknown compounds with crabby, amine, fishy odors were found to predominate in the overall aroma of cooked lobster tail meat. PMID:11559132

  16. Bone formation is not impaired by hibernation (disuse) in black bears Ursus americanus

    USGS Publications Warehouse

    Donahue, S.W.; Vaughan, M.R.; Demers, L.M.; Donahue, H.J.

    2003-01-01

    Disuse by bed rest, limb immobilization or space flight causes rapid bone loss by arresting bone formation and accelerating bone resorption. This net bone loss increases the risk of fracture upon remobilization. Bone loss also occurs in hibernating ground squirrels, golden hamsters, and little brown bats by arresting bone formation and accelerating bone resorption. There is some histological evidence to suggest that black bears Ursus americanus do not lose bone mass during hibernation (i.e. disuse). There is also evidence suggesting that muscle mass and strength are preserved in black bears during hibernation. The question of whether bears can prevent bone loss during hibernation has not been conclusively answered. The goal of the current study was to further assess bone metabolism in hibernating black bears. Using the same serum markers of bone remodeling used to evaluate human patients with osteoporosis, we assayed serum from five black bears, collected every 10 days over a 196-day period, for bone resorption and formation markers. Here we show that bone resorption remains elevated over the entire hibernation period compared to the pre-hibernation period, but osteoblastic bone formation is not impaired by hibernation and is rapidly accelerated during remobilization following hibernation.

  17. Temperature and acid-base balance in the American lobster Homarus americanus.

    PubMed

    Qadri, Syed Aman; Camacho, Joseph; Wang, Hongkun; Taylor, Josi R; Grosell, Martin; Worden, Mary Kate

    2007-04-01

    Lobsters (Homarus americanus) in the wild inhabit ocean waters where temperature can vary over a broad range (0-25 degrees C). To examine how environmental thermal variability might affect lobster physiology, we examine the effects of temperature and thermal change on the acid-base status of the lobster hemolymph. Total CO(2), pH, P(CO)2 and HCO(-)(3) were measured in hemolymph sampled from lobsters acclimated to temperature in the laboratory as well as from lobsters acclimated to seasonal temperatures in the wild. Our results demonstrate that the change in hemolymph pH as a function of temperature follows the rule of constant relative alkalinity in lobsters acclimated to temperature over a period of weeks. However, thermal change can alter lobster acid-base status over a time course of minutes. Acute increases in temperature trigger a respiratory compensated metabolic acidosis of the hemolymph. Both the strength and frequency of the lobster heartbeat in vitro are modulated by changes in pH within the physiological range measured in vivo. These observations suggest that changes in acid-base status triggered by thermal variations in the environment might modulate lobster cardiac performance in vivo.

  18. Sarcocystis oreamni, n. sp. (Apicomplexa: Sarcocystidae) from the mountain goat (Oreamnos americanus).

    PubMed

    Calero-Bernal, Rafael; Van Wilpe, Erna; White, Kevin; Verma, Shiv K; Cerqueira-Cézar, Camila K; Dubey, Jitender P

    2015-11-01

    Numerous species of Sarcocystis have been reported from wild ruminants, but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of three of seven mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; one had Sarcocystis cornagliai-like sarcocysts, previously named from the Alpine ibex (Capra ibex) from Europe. Two other goats were infected with a new species, Sarcocystis oreamni. Sarcocystis oreamni sarcocysts were microscopic with 2 μm-thick sarcocyst wall. By transmission electron microscopy, the sarcocyst wall had 1.7 μm-thick with unusual molar tooth-like villar protrusions (vp), type 29. The vp had an electron dense core and two disc-shaped plaques at the tip with fine microtubules. Bradyzoites were 8.6-9.1 μm long. Single nucleotide polymorphism (SNP) identified in 18S rRNA, and 28S rRNA loci of rDNA regions that suggested S. oreamni molecularly apart from related species. The phylogenetic analysis based on 18S rRNA and 28S rRNA sequences suggested S. oreamni is related with Sarcocystis species that employ members of the Canidae family as their definitive host. PMID:26255900

  19. Temporal dynamics of genetic variability in a mountain goat (Oreamnos americanus) population.

    PubMed

    Ortego, Joaquín; Yannic, Glenn; Shafer, Aaron B A; Mainguy, Julien; Festa-Bianchet, Marco; Coltman, David W; Côté, Steeve D

    2011-04-01

    The association between population dynamics and genetic variability is of fundamental importance for both evolutionary and conservation biology. We combined long-term population monitoring and molecular genetic data from 123 offspring and their parents at 28 microsatellite loci to investigate changes in genetic diversity over 14 cohorts in a small and relatively isolated population of mountain goats (Oreamnos americanus) during a period of demographic increase. Offspring heterozygosity decreased while parental genetic similarity and inbreeding coefficients (F(IS) ) increased over the study period (1995-2008). Immigrants introduced three novel alleles into the population and matings between residents and immigrants produced more heterozygous offspring than local crosses, suggesting that immigration can increase population genetic variability. The population experienced genetic drift over the study period, reflected by a reduced allelic richness over time and an 'isolation-by-time' pattern of genetic structure. The temporal decline of individual genetic diversity despite increasing population size probably resulted from a combination of genetic drift due to small effective population size, inbreeding and insufficient counterbalancing by immigration. This study highlights the importance of long-term genetic monitoring to understand how demographic processes influence temporal changes of genetic diversity in long-lived organisms. PMID:21366746

  20. American Lobsters (Homarus Americanus) not Surviving During Air Transport: Evaluation of Microbial Spoilage

    PubMed Central

    Tirloni, Erica; Stella, Simone; Gennari, Mario; Colombo, Fabio

    2016-01-01

    Eighteen American lobsters (Homarus americanus), dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of American lobsters’ meats in terms of spoilage microbiota. The meat samples showed very limited total viable counts, in almost all the cases below the level of 6 Log CFU/g, while higher loads were found, as expected, in gut and gills, the most probable source of contamination. These data could justify the possibility to commercialise these not-surviving subjects, without quality concerns for the consumers. Most of the isolates resulted to be clustered with type strains of Pseudoalteromonas spp. (43.1%) and Photobacterium spp. (24.1%), and in particular to species related to the natural marine environment. The distribution of the genera showed a marked inhomogeneity among the samples. The majority of the isolates identified resulted to possess proteolytic (69.3%) and lipolytic ability (75.5%), suggesting their potential spoilage ability. The maintanance of good hygienical practices, especially during the production of ready-to-eat lobsters-based products, and a proper storage could limit the possible replication of these microorganisms. PMID:27800442

  1. Behavior and substrate selection during larval settling in the lobster Homarus americanus

    SciTech Connect

    Botero, L.; Atema, J.

    1982-02-01

    During the molt from third- to fourth-stage, larvae of Homarus americanus metamorphose into their adult form and pigmentation. In the course of the fourth stage, their pelagic life changes to a benthic existence. Artificial substrate choice experiments and qualitative illumination experiments show that during the early fourth stage the phototactic response reverses from positive to negative. Together with positive thigmotaxis, this results in a choice of dark crevices. Among natural substrate choices, preferential settlement occurred on macroalgal-covered rocks, followed by rocks on sand, mud, and sand. Although mud was not a preferred substrate in choice tests, the animals that chose mud and those that were presented only with mud settled successfully and were immediately efficient in their burrowing behavior, constructing U-shaped tunnels even in the center of the aquarium without using a pebble or rock as a starting point. These laboratory test confirm field observations that lobsters can successfully exploit a variety of substrates. They show that a substrate with preformed crevices is preferred for settling, but other substrates can be manipulated to make suitable burrows.

  2. Electrogenic sulfate uptake by crustacean hepatopancreatic basolateral membrane vesicles. [Homarus americanus

    SciTech Connect

    Cattey, M.A.; Gerencser, G.A.; Aheam, G.A. Univ. of Florida, Gainesville )

    1990-02-26

    Basolateral membrane vesicles (BLMV) were isolated from Atlantic lobster (Homarus americanus) hepatopancreas and purified by discontinuous sucrose gradient centrifugation. BLMV prepared in this fashion were osmotically reactive exhibiting linear dependence of vesicular {sup 35}SO{sub 4}{sup {minus}2} uptake to increasing external osmotic pressure with negligible non-specific isotope binding. Under short circuited conditions (valinomycin/K{sup +}) BLMV responded to either a HCO{sub 3}{sup {minus}} gradient directed out or equilibrated HCO{sub 3}{sup {minus}} (10 mM) by displaying short term accumulation of sulfate above that of equilibrium. Uptake of divalent anion was unaffected by an inwardly directed transmembrane Na{sup +} or tetramethylammonium{sup +} gradient. {sup 35}SO{sub 4}{sup {minus}2}/HCO{sub 3}{sup {minus}} exchange in the presence of valinomycin was stimulated by transient inside positive K{sup +} diffusion potentials and inhibited by transient inside negative K{sup +} diffusion potentials. The role of electrogenic anion exchange by hepatopancreas BLMV in transcellular sulfate transport is discussed.

  3. Sulfate uptake by crustacean hepatopancreatic brush border membrane vesicles. [Homarus americanus

    SciTech Connect

    Gerencser, G.A.; Cattey, M.A; Ahearn, G.A. Univ. of Hawaii, Honolulu )

    1990-02-26

    Purified brush border membrane vesicles (BBMV) were prepared from Atlantic lobster (Homarus americanus) hepatopancreas using differential centrifugation and Mg{sup +2} precipitation techniques. Uptake of 0.1 mM {sup 35}SO{sub 4}{sup {minus}2} was stimulated by pre-loading vesicles with Cl{sup {minus}} leading to a transient accumulation of isotope more than twice that at equilibrium. Pre-loading with HCO{sub 3}{sup {minus}} or gluconate had no effect on sulfate uptake. No stimulation of {sup 35}SO{sub 4}{sup {minus}2} was observed in the presence of inwardly directed Na{sup +} or tetramethylammonium{sup +} gradients. Uptake of the divalent anion was strongly stimulated by inwardly directed proton gradients (pH{sub o} < pH{sub i}) and markedly inhibited by outwardly directed proton gradients (pH{sub o} > pH{sub i}). {sup 35}SO{sub 4}{sup {minus}2}/Cl{sup {minus}} exchange was enhanced by imposing a transmembrane inside positive K{sup +} diffusion potential and inhibited by a membrane potential of the opposite polarity (K{sup +}/valinomycin). Results suggest the presence of a proton-dependent, electrogenic anion antiport mechanism in BBMV isolated from the crustacean hepatopancreas.

  4. Antifreeze proteins from the sea raven, Hemitripterus americanus. Further evidence for diversity among fish polypeptide antifreezes

    SciTech Connect

    Slaughter, D.; Fletcher, G.L.; Ananthanarayanan, V.S.; Hew, C.L.

    1981-02-25

    The antifreeze proteins of the sea raven, Hemitripterus americanus, were isolated and compared with other fish antifreeze proteins. The sea raven contains one major protein of molecular weight 14,000-16,000 with little or no carbohydrate. Except for its similar seasonal appearance, the sea raven antifreeze protein differs from other polypeptide antifreeze in its amino acid composition, secondary structure, and immunological specificity. Amino acid analysis of sea raven antifreeze showed that it contains a high amount of half-cystine, hydrophilic amino acids, and only an average amount of alanine. In contrast, all other fish antifreeze proteins contain approximately 60% alanine and no half-cystine residues. Furthermore, the sea raven antifreeze protein is sensitive to sulfhydryl reagents. The antifreeze activity was decreased by 67% in the presence of 0.01 M dithiothreitol. Circular dichroism studies indicated the absence of significant amounts of ..cap alpha..-helix and the possible presence of ..beta..-structure. Antibodies raised against the antifreeze protein did not cross-react with the known polypeptide antifreeze from the winter flounder and shorthorn sculpin (Hew, C.L., Fletcher, G.L., and Ananthanarayanan, V.S. (1980) Can. J. Biochem. 58, 377-383). A specific radioimmunoassay was developed for the sea raven antifreeze protein and was used to quantitate the protein concentration in the fish. The seasonal profile obtained by radioimmunoassay was compatible with the antifreeze activity determined with a freezing point osmometer.

  5. Daily Rhythms of PERIOD protein in the eyestalk of the American lobster, Homarus americanus.

    PubMed

    Grabek, Katharine R; Chabot, Christopher C

    2012-01-01

    The daily rhythm of PERIOD protein (PER) expression is an integral component of the circadian clock, which is found among a broad range of animal species including fruit flies, marine mollusks and even humans. The use of antibodies directed against PER has provided a helpful tool in the discovery of PER homologues and the labeling of putative pacemaker cells, especially in animals for which an annotated genome is not readily available. In this study, DrosophilaPER antibodies were used to probe for PER in the American lobster, Homarus americanus. This species exhibits robust endogenous circadian rhythms but the circadian clock has yet to be located or characterized. PER was detected in the eyestalks of the lobster but not in the brain. Furthermore, a significant effect of the LD cycle on daily PER abundance was identified, and PER was significantly more abundant at mid dark than in early light or mid light hours. Our results suggest that PER is a part of the molecular machinery of the circadian clock located in the eyestalk of the lobster.

  6. An unusual cuticular tumor-like growth on the abdomen of a lobster, Homarus americanus.

    PubMed

    Shields, Jeffrey D; Small, Hamish J

    2013-11-01

    Tumors are rare in crustaceans, and whereas a few have been reported from the lobster Homarus americanus none have been adequately described. A lobster with an unusual, large, blue-colored tumor-like growth projecting laterally outward from the first abdominal somite was caught off Stonington, Maine, USA. The growth was rugose and covered by a relatively normal appearing cuticle with dispersed focal melanization. The underlying stroma consisted of an internal area of rescaffolded fibrous connective tissue, restructured muscle fibers, few arterioles, and an epidermal area comprised of columnar, highly vacuolated epithelial cells. No infectious pathogens or unusual inclusions were observed with microscopy and no eukaryotic pathogens were detected via molecular sequencing. Given the nature of the histology and the appearance of the growth, we identify the mass as a benign papilliform hamartoma that likely originated as a result of abnormal wound repair possibly initiated around ecdysis. This represents the first tumor-like hamartoma reported from a lobster, and the second hamartoma reported from a crustacean.

  7. Experimental infection and detection of necrotizing hepatopancreatitis bacterium in the American lobster Homarus americanus.

    PubMed

    Avila-Villa, Luz A; Gollas-Galván, Teresa; Martínez-Porchas, Marcel; Mendoza-Cano, Fernando; Hernández-López, Jorge

    2012-01-01

    Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo.

  8. Antimicrobial activity in the cuticle of the American lobster, Homarus americanus.

    PubMed

    Mars Brisbin, Margaret; McElroy, Anne E; Pales Espinosa, Emmanuelle; Allam, Bassem

    2015-06-01

    American lobster, Homarus americanus, continues to be an ecologically and socioeconomically important species despite a severe decline in catches from Southern New England and Long Island Sound (USA) and a high prevalence of epizootic shell disease in these populations. A better understanding of lobster immune defenses remains necessary. Cuticle material collected from Long Island Sound lobsters was found to be active against a broad spectrum of bacteria, including Gram-negative and -positive species. The antimicrobial activity was characterized by boiling, muffling, and size fractioning. Boiling did not significantly reduce activity, while muffling did have a significant effect, suggesting that the active component is organic and heat stable. Size fractioning with 3 and 10 kDa filters did not significantly affect activity. Fast protein liquid chromatography fractions were also tested for antimicrobial activity, and fractions exhibiting protein peaks remained active. MALDI mass spectrometry revealed peptide peaks at 1.6, 2.8, 4.6, and 5.6 kDa. The data presented suggest that one or several antimicrobial peptides contribute to antimicrobial activity present in the American lobster cuticle.

  9. Anaerobic oral flora in the North American black bear (Ursus americanus) in eastern North Carolina.

    PubMed

    Clarke, Elsburgh O; Stoskopf, Michael K; Minter, Larry J; Stringer, Elizabeth M

    2012-06-01

    Microbial flora can provide insight into the ecology and natural history of wildlife in addition to improving understanding of health risks. This study examines the anaerobic oral flora of hunter killed black bears (Ursus americanus) in eastern North Carolina. Oral swabs from the buccal and lingual supragingival tooth surfaces of the first and second mandibular and maxillary molars of 22 black bears were inoculated onto Brucella Blood Agar plates supplemented with hemin and vitamin K after transport from the field using reduced oxoid nutrient broth. Sixteen anaerobic bacterial species, representing nine genera were identified using the RapID ANA II Micromethod Kit system and a number of organisms grown that could not be identified with the system. The most frequently identified anaerobes were Peptostreptococcus prevotii, Streptococcus constellatus, and Porphyromonas gingivalis. The diversity in the anaerobic oral flora of black bear in eastern North Carolina suggests the importance of including these organisms in basic health risk assessment protocols and suggests a potential tool for assessment of bear/habitat interactions. PMID:22503889

  10. Serosurvey for selected pathogens in free-ranging American black bears (Ursus americanus) in Maryland, USA.

    PubMed

    Bronson, Ellen; Spiker, Harry; Driscoll, Cindy P

    2014-10-01

    American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Maryland counties and tested them for exposure to infectious, including zoonotic, pathogens. A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower. Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsii, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis. Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied. Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health. PMID:25075540

  11. Bears "Count" Too: Quantity Estimation and Comparison in Black Bears (Ursus Americanus).

    PubMed

    Vonk, Jennifer; Beran, Michael J

    2012-07-01

    Studies of bear cognition are notably missing from the comparative record despite bears' large relative brain size and interesting status as generalist carnivores facing complex foraging challenges, but lacking complex social structures. We investigated the numerical abilities of three American black bears (Ursus Americanus) by presenting discrimination tasks on a touch-screen computer. One bear chose the larger of two arrays of dot stimuli, while two bears chose the smaller array of dots. On some trials the relative number of dots was congruent with the relative total area of the two arrays. On other trials number of dots was incongruent with area. All of the bears were above chance on trials of both types with static dots. Despite encountering greater difficulty with dots that moved within the arrays, one bear was able to discriminate numerically larger arrays of moving dots, and a subset of moving dots from within the larger array, even when area and number were incongruent. Thus, although the bears used area as a cue to guide responding, they were also able to use number as a cue. The pattern of performance was similar to that found previously with monkeys, and suggests that bears may also show other forms of sophisticated quantitative abilities. PMID:22822244

  12. Temporal dynamics of genetic variability in a mountain goat (Oreamnos americanus) population.

    PubMed

    Ortego, Joaquín; Yannic, Glenn; Shafer, Aaron B A; Mainguy, Julien; Festa-Bianchet, Marco; Coltman, David W; Côté, Steeve D

    2011-04-01

    The association between population dynamics and genetic variability is of fundamental importance for both evolutionary and conservation biology. We combined long-term population monitoring and molecular genetic data from 123 offspring and their parents at 28 microsatellite loci to investigate changes in genetic diversity over 14 cohorts in a small and relatively isolated population of mountain goats (Oreamnos americanus) during a period of demographic increase. Offspring heterozygosity decreased while parental genetic similarity and inbreeding coefficients (F(IS) ) increased over the study period (1995-2008). Immigrants introduced three novel alleles into the population and matings between residents and immigrants produced more heterozygous offspring than local crosses, suggesting that immigration can increase population genetic variability. The population experienced genetic drift over the study period, reflected by a reduced allelic richness over time and an 'isolation-by-time' pattern of genetic structure. The temporal decline of individual genetic diversity despite increasing population size probably resulted from a combination of genetic drift due to small effective population size, inbreeding and insufficient counterbalancing by immigration. This study highlights the importance of long-term genetic monitoring to understand how demographic processes influence temporal changes of genetic diversity in long-lived organisms.

  13. Sarcocystis oreamni, n. sp. (Apicomplexa: Sarcocystidae) from the mountain goat (Oreamnos americanus).

    PubMed

    Calero-Bernal, Rafael; Van Wilpe, Erna; White, Kevin; Verma, Shiv K; Cerqueira-Cézar, Camila K; Dubey, Jitender P

    2015-11-01

    Numerous species of Sarcocystis have been reported from wild ruminants, but none has been named from the Rocky Mountain goat (Oreamnos americanus). Mature sarcocysts were found in frozen muscle samples of three of seven mountain goats from Alaska, USA. Two morphological types of sarcocysts were found; one had Sarcocystis cornagliai-like sarcocysts, previously named from the Alpine ibex (Capra ibex) from Europe. Two other goats were infected with a new species, Sarcocystis oreamni. Sarcocystis oreamni sarcocysts were microscopic with 2 μm-thick sarcocyst wall. By transmission electron microscopy, the sarcocyst wall had 1.7 μm-thick with unusual molar tooth-like villar protrusions (vp), type 29. The vp had an electron dense core and two disc-shaped plaques at the tip with fine microtubules. Bradyzoites were 8.6-9.1 μm long. Single nucleotide polymorphism (SNP) identified in 18S rRNA, and 28S rRNA loci of rDNA regions that suggested S. oreamni molecularly apart from related species. The phylogenetic analysis based on 18S rRNA and 28S rRNA sequences suggested S. oreamni is related with Sarcocystis species that employ members of the Canidae family as their definitive host.

  14. Energy expenditure during activity in the American lobster Homarus americanus: Correlations with body acceleration.

    PubMed

    Lyons, G N; Halsey, L G; Pope, E C; Eddington, J D; Houghton, J D R

    2013-10-01

    How animals manage time and expend energy has implications for survivorship. Being able to measure key metabolic costs of animals under natural conditions is therefore an important tool in behavioral ecology. One method for estimating activity-specific metabolic rate is via derived measures of acceleration, often 'overall dynamic body acceleration' (ODBA), recorded by an instrumented acceleration logger. ODBA has been shown to correlate well with rate of oxygen consumption (V˙o2) in a range of species during activity in the laboratory. This study devised a method for attaching acceleration loggers to decapod crustaceans and then correlated ODBA against concurrent respirometry readings to assess accelerometry as a proxy for activity-specific energy expenditure in a model species, the American lobster Homarus americanus. Where the instrumented animals exhibited a sufficient range of activity levels, positive linear relationships were found between V˙o2 and ODBA over 20min periods at a range of ambient temperatures (6, 13 and 20°C). Mixed effect linear models based on these data and morphometrics provided reasonably strong predictive power for estimating activity-specific V˙o2 from ODBA. These V˙o2-ODBA calibrations demonstrate the potential of accelerometry as an effective predictor of behavior-specific metabolic rate of crustaceans in the wild during periods of activity.

  15. Effects of cooking on levels of PCBs in the fillets of winter flounder (Pseudopleuronectes americanus)

    SciTech Connect

    Poston, T.M.; Durell, G.S.; Koczwara, G.; Spellacy, A.M.

    1995-08-01

    The Pacific Northwest Laboratory and Battelle Ocean Sciences performed a study to determine the effect of cooking on polychlorinated biphenyl (PCB) levels in the fillets of winter flounder (Pseudopleuronectes americanus). Broiling, pan frying, and deep frying in oil were tested on fillets from 21 fish collected from New Bedford Harbor, Massachusetts, on February 21, 1991. The evaluation involved estimating the change in PCB concentrations using a mass-balance approach that factored the change in fillet weight resulting from cooking with the changes in PCB concentration expressed on a precooked wet-weight basis. Deep frying in oil resulted in a 47% reduction in total PCB levels in fillet tissue. Additionally, deep frying caused a 40% reduction in fillet mass. Pan frying and broiling resulted in statistically in insignificant increases in total PCB levels of 15% and 17%, respectively. Fillet mass reductions resulting from pan frying and broiling were 7% and 15%, respectively. The effects of cooking on 18 individual congeners generally paralleled the results observed for total PCB. All 18 congeners were significantly reduced by deep frying. Congener Cl{sub 2}(08) also was significantly reduced by either pan frying. Congeners Cl{sub 5}(105) and Cl{sub 5}(118) showed apparent significant increases in concentrations following pan frying. Congeners Cl{sub 5}(105), Cl{sub 5}(118), and C1{sub 6}(138) showed significant increases in concentration following broiling.

  16. Bears “Count” Too: Quantity Estimation and Comparison in Black Bears (Ursus Americanus)

    PubMed Central

    Vonk, Jennifer; Beran, Michael J.

    2012-01-01

    Studies of bear cognition are notably missing from the comparative record despite bears’ large relative brain size and interesting status as generalist carnivores facing complex foraging challenges, but lacking complex social structures. We investigated the numerical abilities of three American black bears (Ursus Americanus) by presenting discrimination tasks on a touch-screen computer. One bear chose the larger of two arrays of dot stimuli, while two bears chose the smaller array of dots. On some trials the relative number of dots was congruent with the relative total area of the two arrays. On other trials number of dots was incongruent with area. All of the bears were above chance on trials of both types with static dots. Despite encountering greater difficulty with dots that moved within the arrays, one bear was able to discriminate numerically larger arrays of moving dots, and a subset of moving dots from within the larger array, even when area and number were incongruent. Thus, although the bears used area as a cue to guide responding, they were also able to use number as a cue. The pattern of performance was similar to that found previously with monkeys, and suggests that bears may also show other forms of sophisticated quantitative abilities. PMID:22822244

  17. Behavioral response and kinetics of terrestrial atrazine exposure in American toads (bufo americanus)

    USGS Publications Warehouse

    Storrs, Mendez S.I.; Tillitt, D.E.; Rittenhouse, T.A.G.; Semlitsch, R.D.

    2009-01-01

    Amphibians in terrestrial environments obtain water through a highly vascularized pelvic patch of skin. Chemicals can also be exchanged across this patch. Atrazine (ATZ), a widespread herbicide, continues to be a concern among amphibian ecologists based on potential exposure and toxicity. Few studies have examined its impact on the terrestrial juvenile or adult stages of toads. In the current study, we asked the following questions: (1) Will juvenile American toads (Bufo americanus) avoid soils contaminated with ATZ? (2) Can they absorb ATZ across the pelvic patch? (3) If so, how is it distributed among the organs and eventually eliminated? We conducted a behavioral choice test between control soil and soil dosed with ecologically relevant concentrations of ATZ. In addition, we examined the uptake, distribution, and elimination of water dosed with 14C-labeled ATZ. Our data demonstrate that toads do not avoid ATZ-laden soils. ATZ crossed the pelvic patch rapidly and reached an apparent equilibrium within 5 h. The majority of the radiolabeled ATZ ended up in the intestines, whereas the greatest concentrations were observed in the gall bladder. Thus, exposure of adult life stages of amphibians through direct uptake of ATZ from soils and runoff water should be considered in risk evaluations. ?? 2009 Springer Science+Business Media, LLC.

  18. Antimicrobial activity in the cuticle of the American lobster, Homarus americanus.

    PubMed

    Mars Brisbin, Margaret; McElroy, Anne E; Pales Espinosa, Emmanuelle; Allam, Bassem

    2015-06-01

    American lobster, Homarus americanus, continues to be an ecologically and socioeconomically important species despite a severe decline in catches from Southern New England and Long Island Sound (USA) and a high prevalence of epizootic shell disease in these populations. A better understanding of lobster immune defenses remains necessary. Cuticle material collected from Long Island Sound lobsters was found to be active against a broad spectrum of bacteria, including Gram-negative and -positive species. The antimicrobial activity was characterized by boiling, muffling, and size fractioning. Boiling did not significantly reduce activity, while muffling did have a significant effect, suggesting that the active component is organic and heat stable. Size fractioning with 3 and 10 kDa filters did not significantly affect activity. Fast protein liquid chromatography fractions were also tested for antimicrobial activity, and fractions exhibiting protein peaks remained active. MALDI mass spectrometry revealed peptide peaks at 1.6, 2.8, 4.6, and 5.6 kDa. The data presented suggest that one or several antimicrobial peptides contribute to antimicrobial activity present in the American lobster cuticle. PMID:25804485

  19. Social network analysis of mating patterns in American black bears (Ursus americanus).

    PubMed

    Moore, Jennifer A; Xu, Ran; Frank, Kenneth; Draheim, Hope; Scribner, Kim T

    2015-08-01

    Nonrandom mating can structure populations and has important implications for population-level processes. Investigating how and why mating deviates from random is important for understanding evolutionary processes as well as informing conservation and management. Prior to the implementation of parentage analyses, understanding mating patterns in solitary, elusive species like bears was virtually impossible. Here, we capitalize on a long-term genetic data set collected from black bears (Ursus americanus) (N = 2422) in the Northern Lower Peninsula (NLP) of Michigan, USA. We identified mated pairs using parentage analysis and applied logistic regression (selection) models that controlled for features of the social network, to quantify the effects of individual characteristics, and spatial and population demographic factors on mating dynamics. Logistic regression models revealed that black bear mating was associated with spatial proximity of mates, male age, the time a pair had coexisted, local population density and relatedness. Mated pairs were more likely to contain older males. On average, bears tended to mate with nearby individuals to whom they were related, which does not support the existence of kin recognition in black bears. Pairwise relatedness was especially high for mated pairs containing young males. Restricted dispersal and high male turnover from intensive harvest mortality of NLP black bears are probably the underlying factors associated with younger male bears mating more often with female relatives. Our findings illustrate how harvest has the potential to disrupt the social structure of game species, which warrants further attention for conservation and management.

  20. Liver lesions in winter flounder (Pseudopleuronectes americanus) from Jamaica Bay, New York: Indications of environmental degradation

    USGS Publications Warehouse

    Augspurger, T.P.; Herman, R.L.; Tanacredi, J.T.; Hatfield, J.S.

    1994-01-01

    Liver sections of winter flounder (Pseudopleuronectes americanus) collected from Jamaica Bay and Shinnecock Bay, New York, in 1989, were examined microscopically to determine the pervasiveness of liver lesions observed previously in Jamaica Bay winter flounder. Neoplastic lesions were not detected in fish from Jamaica Bay or the Shinnecock Bay reference site. Twenty-two percent of Jamaica Bay winter flounder examined (n = 103) had unusual vacuolization of hepatocytes and biliary pre-ductal and ductal cells (referred to hereafter as the vacuolated cell lesion). The lesion, identical to that found in 25% of Jamaica Bay winter flounder examined in 1988, has previously been identified in fishes taken from highly polluted regions of the Atlantic coast (e.g., Boston Harbor, Massachusetts, and Black Rock Harbor, Connecticut). Prevalence of the vacuolated cell lesion in winter flounder from Jamaica Bay was significantly greater (p < 0.0001) than in 102 specimens collected from Shinnecock Bay. Current scientific literature indicates vacuolated hepatocytes and cholangiocytes are chronically injured and that the extent of their deformity is consistent with the action of a hepatotoxicant. The high prevalence of vacuolated hepatocytes in Jamaica Bay winter flounder and absence of the lesion in flounder from reference sites strongly supports the hypothesis that this impairment is a manifestation of a toxic condition in at least some portions of Jamaica Bay.

  1. Necator americanus secretory acetylcholinesterase and its purification from excretory-secretory products by affinity chromatography.

    PubMed

    Pritchard, D I; Leggett, K V; Rogan, M T; McKean, P G; Brown, A

    1991-03-01

    Acetylcholinesterase (AChE) secretion by adult N. americanus was enhanced in vitro by incorporating insoluble collagen rafts into culture dishes. Enzyme produced in this way had preferential substrate specificity for acetylthiocholine iodide (ATC), and its activity was inhibited by eserine (1.1 x 10(-8) M). Ancylostoma ceylanicum, another hookworm species, failed to produce comparable amounts of AChE in culture. AChE was efficiently purified from culture medium by affinity chromatography on edrophonium sepharose; 81% of the AChE activity was retained by the affinity matrix, although this fraction contained only 4.3% of the protein loaded. Antisera raised against purified AChE in rabbits immunohistochemically stained the oesophageal glands of the parasite, and reacted with molecules of 32, 60, 80, 140 and 220 kDa in reduced adult ES products on Western blotting, although differential activity was observed against worm homogenates and earlier developmental stages. On IEF, purified AChE resolved predominantly with a pl of 3.55; proteins with a similar pl were recognized by rabbit anti-AChE. IgG preparations of this antiserum inhibited AChE activity in ES products, and inhibited AChE secretion by adult worms in culture. The availability of this immunological probe will allow definitive experiments to be conducted on the role of this enigmatic enzyme in the host-parasite relationship. PMID:2052405

  2. Measurement of the total flux averaged neutrino induced neutral current elastic scattering cross section with the T2K Pi-Zero detector

    NASA Astrophysics Data System (ADS)

    Ruterbories, Daniel

    Tokai-to-Kamioka (T2K) is a second generation accelerator neutrino oscillation experiment. T2K uses a high intensity proton beam produced at the Japan Proton Accelerator Research Complex (J-PARC) incident on a carbon target and focused with three magnetic horns to produce a high intensity and nearly pure muon neutrino beam with a peak energy of 600 MeV at a 2.5º axis angle. The muon neutrino beam travels 295 km across Japan to the Super Kamiokande (SK) water Cherenkov detector in the Kamioka mine. The neutrino beam is also sampled by a complex of near detectors 280 m downstream of the carbon target located both on and off the beam axis. These detectors measure the neutrino beam before neutrino oscillations occur to provide input constraints to oscillation searches using SK. The off-axis near detector, ND280, is a composite detector made up of a tracker section and a Pi-Zero detector (POD), all surrounded by an electromagnetic calorimeter. The entire detector is enclosed in a dipole magnet with a field of 0.2 T. The primary purpose of the tracker section is to measure neutrino induced charged current events characterized by the production of muons. The POD is primarily designed to detect electromagnetic showers and to measure interactions on water through the use of a removable water target. In addition to these measurements, the ND280 detector is also used to study the cross sections of neutrino interactions on the various materials in the detectors. Limited knowledge of the cross sections in this neutrino energy regime are an important source of systematic error in neutrino oscillation measurements. This thesis presents a measurement of one neutrino interaction channel in the POD, neutral current elastic scattering (NCE). In this process a neutrino elastically scatters off a proton or neutron in the target nucleus producing a proton or neutron with higher energy. The signature of this process is a single proton track. A particle identification algorithm (PID) was

  3. Differential expression of American lobster (Homarus americanus) immune related genes during infection of Aerococcus viridans var. homari, the causative agent of Gaffkemia.

    PubMed

    Clark, K Fraser; Acorn, Adam R; Greenwood, Spencer J

    2013-02-01

    This is the first transcriptomic study focusing on immunity in the commercially valuable American lobster (Homarus americanus). We have conducted an in vivo infection trial using the Gram-positive bacterium Aerococcus viridans var. homari to determine how H. americanus responds to this naturally occurring lethal-pathogen. A novel H. americanus microarray was used to measure the transcriptomic changes occurring in over 14,000 genes in the lobster hepatopancreas. Hundreds of new immune genes and isoforms were identified and measured for the first time in this species, and our findings highlight 148 genes of interest involved in H. americanus pathogen response. We verified our microarray results using RT-qPCR on three anti-lipopolysaccharide (ALFHa-1, ALFHa-2, ALFHa-4), a thioredoxin, acute phase serum amyloid protein A, hexokinase and two trypsin genes. RT-qPCR and microarray findings show close agreement and highlight the significant increase in gene expression in many lobster immune genes during A. viridans infection. Differential expression of the ALFHa isoforms may indicate that the H. americanus immune response can be tailored to the class of pathogen causing disease.

  4. Neutral beam monitoring

    DOEpatents

    Fink, Joel H.

    1981-08-18

    Method and apparatus for monitoring characteristics of a high energy neutral beam. A neutral beam is generated by passing accelerated ions through a walled cell containing a low energy neutral gas, such that charge exchange neutralizes the high energy ion beam. The neutral beam is monitored by detecting the current flowing through the cell wall produced by low energy ions which drift to the wall after the charge exchange. By segmenting the wall into radial and longitudinal segments various beam conditions are further identified.

  5. Intranasal vaccination of recombinant H5N1 HA1 proteins fused with foldon and Fc induces strong mucosal immune responses with neutralizing activity: Implication for developing novel mucosal influenza vaccines

    PubMed Central

    Yu, Fei; Li, Ye; Guo, Yan; Wang, Lili; Yang, Jie; Zhao, Guangyu; Zhou, Yusen; Du, Lanying; Jiang, Shibo

    2015-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 virus remains a threat to public health because of its continued spread in poultry in some countries and its ability to infect humans with high mortality rate, calling for the development of effective and safe vaccines against H5N1 infection. Here, we constructed 4 candidate vaccines by fusing H5N1 hemagglutinin 1 (HA1) with foldon (HA1-Fd), human IgG Fc (HA1-Fc), foldon and Fc (HA1-FdFc) or His-tag (HA1-His). We then compared their ability to induce mucosal immune responses and neutralizing antibodies in the presence or absence of Poly(I:C) and CpG adjuvants via the intranasal route. Without an adjuvant, HA1-FdFc could elicit appreciable humoral immune responses and local mucosal IgA antibodies in immunized mice, while other vaccine candidates only induced background immune responses. In the presence of Poly(I:C) and CpG, both HA1-Fd and HA1-Fc elicited much higher levels of serum IgG and local mucosal IgA antibodies than HA1-His. Poly(I:C) and CpG could also augment the neutralizing antibody responses induced by these 4 vaccine candidates in the order of HA1-FdFc > HA1-Fc > HA1-Fd > HA1-His. These results suggest that both Fd and Fc potentiate the immunogenicity of the recombinant HA1 protein and that Poly(I:C) and CpG serve as efficient mucosal adjuvants in promoting efficacy of these vaccine candidates to induce strong systemic and local antibody responses and potent neutralizing antibodies, providing a useful strategy to develop effective and safe mucosal H5N1 vaccines. PMID:26260706

  6. Intranasal vaccination of recombinant H5N1 HA1 proteins fused with foldon and Fc induces strong mucosal immune responses with neutralizing activity: Implication for developing novel mucosal influenza vaccines.

    PubMed

    Yu, Fei; Li, Ye; Guo, Yan; Wang, Lili; Yang, Jie; Zhao, Guangyu; Zhou, Yusen; Du, Lanying; Jiang, Shibo

    2015-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 virus remains a threat to public health because of its continued spread in poultry in some countries and its ability to infect humans with high mortality rate, calling for the development of effective and safe vaccines against H5N1 infection. Here, we constructed 4 candidate vaccines by fusing H5N1 hemagglutinin 1 (HA1) with foldon (HA1-Fd), human IgG Fc (HA1-Fc), foldon and Fc (HA1-FdFc) or His-tag (HA1-His). We then compared their ability to induce mucosal immune responses and neutralizing antibodies in the presence or absence of Poly(I:C) and CpG adjuvants via the intranasal route. Without an adjuvant, HA1-FdFc could elicit appreciable humoral immune responses and local mucosal IgA antibodies in immunized mice, while other vaccine candidates only induced background immune responses. In the presence of Poly(I:C) and CpG, both HA1-Fd and HA1-Fc elicited much higher levels of serum IgG and local mucosal IgA antibodies than HA1-His. Poly(I:C) and CpG could also augment the neutralizing antibody responses induced by these 4 vaccine candidates in the order of HA1-FdFc > HA1-Fc > HA1-Fd > HA1-His. These results suggest that both Fd and Fc potentiate the immunogenicity of the recombinant HA1 protein and that Poly(I:C) and CpG serve as efficient mucosal adjuvants in promoting efficacy of these vaccine candidates to induce strong systemic and local antibody responses and potent neutralizing antibodies, providing a useful strategy to develop effective and safe mucosal H5N1 vaccines.

  7. Seasonal variability of prey in the stomachs of Astropecten americanus (Echinodermata: Asteroidea) from off southern New England, U.S.A.

    NASA Astrophysics Data System (ADS)

    Franz, David R.; Worley, E. K.

    1982-04-01

    The diet of Astropecten americanus from a location off Nantucket Shoals, Massachusetts, was determined by analysis of stomach contents in May and November. Molluscs, followed by crustaceans, dominated stomach contents. The proportion of molluscan species in the diet differed significantly from the benthos, Juvenile Arctica islandica dominated stomachs in May, but declined sharply in November, probably due in part to predation by Astropecten. Other molluscs, not prevalent in the benthos, were important in stomach contents. Frequency distributions of counts of prey species in a sample of seastar stomachs indicate that some seastars ingest unusually large numbers of certain prey species. A. americanus generally ingests small prey individuals (<4mm) although larger prey are consumed, especially in November. Relatively high selectivity, seasonal shifts in the diversity of stomach contents, and evidence for patch-specific foraging are characteristics of A. americanus which are consistent with general predictions of optimum diet models.

  8. Fatal Caprine arthritis encephalitis virus-like infection in 4 Rocky Mountain goats (Oreamnos americanus).

    PubMed

    Patton, Kristin M; Bildfell, Robert J; Anderson, Mark L; Cebra, Christopher K; Valentine, Beth A

    2012-03-01

    Over a 3.5-year period, 4 Rocky Mountain goats (Oreamnos americanus), housed at a single facility, developed clinical disease attributed to infection by Caprine arthritis encephalitis virus (CAEV). Ages ranged from 1 to 10 years. Three of the goats, a 1-year-old female, a 2-year-old male, and a 5-year-old male, had been fed raw domestic goat milk from a single source that was later found to have CAEV on the premises. The fourth animal, a 10-year-old male, had not ingested domestic goat milk but had been housed with the other 3 Rocky Mountain goats. All 4 animals had clinical signs of pneumonia prior to death. At necropsy, findings in lungs included marked diffuse interstitial pneumonia characterized histologically by severe lymphoplasmacytic infiltrates with massive alveolar proteinosis, interstitial fibrosis, and type II pneumocyte hyperplasia. One animal also developed left-sided hemiparesis, and locally extensive lymphoplasmacytic myeloencephalitis was present in the cranial cervical spinal cord. Two animals had joint effusions, as well as severe lymphoplasmacytic and ulcerative synovitis. Immunohistochemical staining of fixed sections of lung tissue from all 4 goats, as well as spinal cord in 1 affected animal, and synovium from 2 affected animals were positive for CAEV antigen. Serology testing for anti-CAEV antibodies was positive in the 2 goats tested. The cases suggest that Rocky Mountain goats are susceptible to naturally occurring CAEV infection, that CAEV from domestic goats can be transmitted to this species through infected milk and by horizontal transmission, and that viral infection can result in clinically severe multisystemic disease. PMID:22379056

  9. Multilocus heterozygosity, parental relatedness and individual fitness components in a wild mountain goat, Oreamnos americanus population.

    PubMed

    Mainguy, Julien; Côté, Steeve D; Coltman, David W

    2009-05-01

    Matings between relatives lead to a decrease in offspring genetic diversity which can reduce fitness, a phenomenon known as inbreeding depression. Because alpine ungulates generally live in small structured populations and often exhibit a polygynous mating system, they are susceptible to inbreeding. Here, we used marker-based measures of pairwise genetic relatedness and inbreeding to investigate the fitness consequences of matings between relatives in a long-term study population of mountain goats (Oreamnos americanus) at Caw Ridge, Alberta, Canada. We first assessed whether individuals avoided mating with kin by comparing actual and random mating pairs according to their estimated genetic relatedness, which was derived from 25 unlinked polymorphic microsatellite markers and reflected pedigree relatedness. We then examined whether individual multilocus heterozygosity H, used as a measure of inbreeding, was predicted by parental relatedness and associated with yearling survival and the annual probability of giving birth to a kid in adult females. Breeding pairs identified by genetic parentage analyses of offspring that survived to 1 year of age were less genetically related than expected under random matings. Parental relatedness was negatively correlated with offspring H, and more heterozygous yearlings had higher survival to 2 years of age. The probability of giving birth was not affected by H in adult females. Because kids that survived to yearling age were mainly produced by less genetically related parents, our results suggest that some individuals experienced inbreeding depression in early life. Future research will be required to quantify the levels of gene flow between different herds, and evaluate their effects on population genetic diversity and dynamics. PMID:19389162

  10. Sequential ovulation and fertility of polyoestrus in American black bears (Ursus americanus)

    PubMed Central

    Himelright, Brendan M.; Moore, Jenna M.; Gonzales, Ramona L.; Mendoza, Alejandra V.; Dye, Penny S.; Schuett, Randall J.; Durrant, Barbara S.; Read, Betsy A.; Spady, Thomas J.

    2014-01-01

    American black bears (Ursus americanus) are seasonally polyoestrous and exhibit delayed implantation, which may allow equal and independent fertility of recurrent oestruses of a mating season. We postulated that the luteal inactivity during delayed implantation allows bears to have sequential ovulation during a polyoestrous mating season such that each oestrus of a polyoestrous female will have equivalent fertility, and pregnancy would not preclude subsequent ovulation and superfetation. Controlled mating experiments were conducted on semi-free-ranging female American black bears during three mating seasons, wherein females were bred by different male cohorts in each oestrus. Behavioural observation, vulva score ranking, genetic paternity analysis, gross morphology of ovaries and microscopic morphology of diapaused embryos were used to evaluate the fertility of each subsequent oestrus in polyoestrous females. Oestrus duration, number of successful mounts and median vulva scores were similar between first and subsequent oestruses of the season. Polyoestrus occurred in 81.3% of oestrous females, with a 9.7 ± 5.5 day (mean ± SD) inter-oestrous interval. Sequential ovulation was documented in three polyoestrous females, including one that possessed both a corpus haemorrhagicum and a developed corpus luteum. Among polyoestrous dams, four of nine embryos were conceived in the first oestrus and five of nine in the second oestrus. These results indicate that each oestrus of polyoestrous females is capable of fertility, even if the female is already pregnant from a prior oestrus. Although superfetation was not directly observed in the present study, our results strongly suggest the potential of superfetation in the American black bear and provide novel insight into the complex behavioural and physiological breeding mechanisms of bears. Given that most endangered bear species share similar reproductive traits with American black bears, captive breeding programmes

  11. Behavioral Thermoregulation and Trade-Offs in Juvenile Lobster Homarus americanus.

    PubMed

    Nielsen, Travis V; McGaw, Iain J

    2016-02-01

    Water temperature influences the behavior and distribution patterns of both larval and adult American lobster Homarus americanus. However, very little is known about the responses of juvenile lobsters. The juvenile life stage is a critical period; high levels of mortality, combined with specific behavioral responses, can disconnect larval settlement from patterns of abundance of adults. We assessed behavioral thermoregulation in juvenile lobsters, and determined how thermal preferences can be altered by the presence of shelter and food. Juvenile lobsters avoided temperatures higher than 20 °C and lower than 8 °C, and had a mean temperature preference of 16.2 ± 1 °C. This preference was unaffected by prior acclimation, origin (laboratory-raised or wild), or size. When the animals were subjected to a temperature change (5-20 °C), activity rates peaked at 15 °C, and remained stable thereafter. Activity rates did not change when a shelter was added. The addition of food resulted in an increase in activity associated with food handling. When juvenile lobsters were offered a choice between temperature, shelter, and food, they always chose the environment with a shelter, even when it was in a thermally unfavorable temperature. Juveniles also spent more time in a thermally unfavorable environment when food was present; however, acquisition of a shelter was prioritized over food. Although juveniles had a similar thermal preference to adults, they are more vulnerable to predation; the innate shelter-seeking behavior of juveniles overrode their thermal preference. While temperature is an important environmental factor affecting the physiology, distribution, and growth of aquatic ectotherms, our findings suggest that trade-off behaviors occur in order to maintain optimal fitness and survival of the individual.

  12. Structural and Functional Characterization of a Multifunctional Alanine-Rich Peptide Analogue from Pleuronectes americanus

    PubMed Central

    Migliolo, Ludovico; Silva, Osmar N.; Silva, Paula A.; Costa, Maysa P.; Costa, Carolina R.; Nolasco, Diego O.; Barbosa, João A. R. G.; Silva, Maria R. R.; Bemquerer, Marcelo P.; Lima, Lidia M. P.; Romanos, Maria T. V.; Freitas, Sonia M.; Magalhães, Beatriz S.; Franco, Octavio L.

    2012-01-01

    Recently, defense peptides that are able to act against several targets have been characterized. The present work focuses on structural and functional evaluation of the peptide analogue Pa-MAP, previously isolated as an antifreeze peptide from Pleuronectes americanus. Pa-MAP showed activities against different targets such as tumoral cells in culture (CACO-2, MCF-7 and HCT-116), bacteria (Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 25923), viruses (HSV-1 and HSV-2) and fungi (Candida parapsilosis ATCC 22019, Trichophyton mentagrophytes (28d&E) and T. rubrum (327)). This peptide did not show toxicity against mammalian cells such as erythrocytes, Vero and RAW 264.7 cells. Molecular mechanism of action was related to hydrophobic residues, since only the terminal amino group is charged at pH 7 as confirmed by potentiometric titration. In order to shed some light on its structure-function relations, in vitro and in silico assays were carried out using circular dichroism and molecular dynamics. Furthermore, Pa-MAP showed partial unfolding of the peptide changes in a wide pH (3 to 11) and temperature (25 to 95°C) ranges, although it might not reach complete unfolding at 95°C, suggesting a high conformational stability. This peptide also showed a conformational transition with a partial α-helical fold in water and a full α-helical core in SDS and TFE environments. These results were corroborated by spectral data measured at 222 nm and by 50 ns dynamic simulation. In conclusion, data reported here show that Pa-MAP is a potential candidate for drug design against pathogenic microorganisms due to its structural stability and wide activity against a range of targets. PMID:23056574

  13. Sequential ovulation and fertility of polyoestrus in American black bears (Ursus americanus).

    PubMed

    Himelright, Brendan M; Moore, Jenna M; Gonzales, Ramona L; Mendoza, Alejandra V; Dye, Penny S; Schuett, Randall J; Durrant, Barbara S; Read, Betsy A; Spady, Thomas J

    2014-01-01

    American black bears (Ursus americanus) are seasonally polyoestrous and exhibit delayed implantation, which may allow equal and independent fertility of recurrent oestruses of a mating season. We postulated that the luteal inactivity during delayed implantation allows bears to have sequential ovulation during a polyoestrous mating season such that each oestrus of a polyoestrous female will have equivalent fertility, and pregnancy would not preclude subsequent ovulation and superfetation. Controlled mating experiments were conducted on semi-free-ranging female American black bears during three mating seasons, wherein females were bred by different male cohorts in each oestrus. Behavioural observation, vulva score ranking, genetic paternity analysis, gross morphology of ovaries and microscopic morphology of diapaused embryos were used to evaluate the fertility of each subsequent oestrus in polyoestrous females. Oestrus duration, number of successful mounts and median vulva scores were similar between first and subsequent oestruses of the season. Polyoestrus occurred in 81.3% of oestrous females, with a 9.7 ± 5.5 day (mean ± SD) inter-oestrous interval. Sequential ovulation was documented in three polyoestrous females, including one that possessed both a corpus haemorrhagicum and a developed corpus luteum. Among polyoestrous dams, four of nine embryos were conceived in the first oestrus and five of nine in the second oestrus. These results indicate that each oestrus of polyoestrous females is capable of fertility, even if the female is already pregnant from a prior oestrus. Although superfetation was not directly observed in the present study, our results strongly suggest the potential of superfetation in the American black bear and provide novel insight into the complex behavioural and physiological breeding mechanisms of bears. Given that most endangered bear species share similar reproductive traits with American black bears, captive breeding programmes

  14. Thyroid cystadenoma, colloid goiter, and hypothyroidism in an American black bear (Ursus americanus).

    PubMed

    Storms, Timothy N; Beazley, Shelley L; Schumacher, Juergen; Ramsay, Edward C

    2004-03-01

    A 178-kg, 14-yr-old captive female American black bear (Ursus americanus) was examined because of lethargy, inappetance, obesity, and alopecia. Serum chemistry and complete blood count values were within normal limits. Based on serum levels for total thyroxine (T4), free T4 by equilibrium dialysis (fT4ED), and canine thyroid-stimulating hormone concentrations, using assays validated for domestic dogs, hypothyroidism was diagnosed presumptively, and therapy with levothyroxine sodium (0.022 mg/kg p.o. b.i.d.) was initiated. Haircoat, body weight, appetite, and activity level improved within 30 days. The levothyroxine dose was decreased twice (to 0.018 mg/kg p.o. b.i.d. and then to 0.011 mg/kg p.o. b.i.d.) during the course of treatment based on monitoring of serum T4 and fT4ED concentrations. After euthanasia for severe refractory lameness, postmortem examination revealed bilateral thyroid lobe enlargement and a fluid-filled cyst within the right lobe. Histologically, colloid goiter was present in both lobes, and a follicular cystadenoma had replaced one third of the cranial pole of the right lobe. The goiter and cystadenoma likely contributed to the hypothyroid condition in this bear and fT4ED was a more sensitive indicator of hypothyroidism than was T4. The recommended canine dosage of levothyroxine may be too high for the treatment of hypothyroidism in American black bears; 0.011 mg/kg p.o. b.i.d. may be a more appropriate dosage. PMID:15193079

  15. Plasma levels of ursodeoxycholic acid in black bears, Ursus americanus: seasonal changes.

    PubMed

    Solá, Susana; Garshelis, David L; Amaral, Joana D; Noyce, Karen V; Coy, Pam L; Steer, Clifford J; Iaizzo, Paul A; Rodrigues, Cecília M P

    2006-06-01

    To date, no other studies have examined the seasonal changes in circulating levels of various bile acids in the plasma of wild North American black bears, Ursus americanus. Using gas chromatography, bile acid concentrations were measured in plasma samples obtained during either early or late hibernation, and during summer active periods. Thus, specific compositional changes from individual animals were examined through a given year. Total bile acid concentrations in the plasma of these normal animals were found to range between 0.2 and 3.1 micromol/L (0.9 +/- 0.2 micromol/L, mean +/- SEM). Cholic, ursodeoxycholic and chenodeoxycholic acids were the major bile acid species identified. Ursodeoxycholic acid represented 28.0 +/- 2.6% of the total bile acid pool. Deoxycholic and lithocholic acids were found only in small amounts. In addition, total bile acid concentrations were lower in plasma samples obtained during hibernation compared with those obtained during summer active periods (0.6 +/- 0.1 and 1.2 +/- 0.4 micromol/L, respectively; p < 0.05). However, the relative proportion of ursodeoxycholic acid, was significantly greater in winter than in summer (31.5 +/- 3.2% and 22.2 +/- 4.5%, p < 0.05). Finally, taurine-conjugated bile acids were the predominant species in bear plasma, accounting for >67% of the total bile acids. These data demonstrate that ursodeoxycholic acid is a major bile acid in black bear plasma, mostly conjugated with taurine. Further, the finding of seasonal variation in plasma bile acid composition provides evidence to support the possible role that ursodeoxycholic acid may play in cellular protection in hibernating black bears. PMID:16571381

  16. Multidisciplinary assessment of pollution at three sites in Long Island Sound. [Pseudopleuronectes americanus

    SciTech Connect

    Gronlund, W.D.; Sinlam Chan; McCain, B.B.; Clark, R.C. Jr.; Myers, M.S.; Stein, J.E.; Brown, D.W.; Landahl, J.T.; Krahn, M.M.; Varanasi, U. )

    1991-09-01

    Winter flounder (Pseudopleuronectes americanus) were sampled from three sites located near Norwalk, New Haven, and Niantic, Connecticut, in Long Island Sound during February 1987, to evaluate the degree of chemical contamination and to determine possible effects of contaminant exposure. At each site, sediment ad infaunal invertebrates were also collected and analyzed for trace metals and organic chemicals. Specimens of liver and kidney from winter flounder were examined for histopathological conditions, including the presence of macrophage aggregates in liver tissue. Liver samples were also analyzed for DNA damage (i.e., the formation of adducts between DNA and chemical contaminants). Blood samples were collected and analyzed for erythrocyte micronuclei. The sampling site near New Haven was determined to be the most affected site, from the standpoints of greater chemical contamination and possible effects on winter flounder. Concentrations of aromatic hydrocarbons (AHs) and polychlorinated biphenyls (PCBs) were highest in sediment from this site, and the highest prevalences of the histopathological changes and DNA alterations were also found in the livers of winter flounder from this site. No differences in the concentrations of contaminants in fish or in frequencies of erythrocyte micronuclei in fish blood were found between sites. None of the sites samples had contaminant levels or prevalences of lesions as high as previously found at other East Coast locations (e.g., Boston Harbor, Massachusetts, Raritan Bay, New York). Overall, the results indicate moderate levels of pollution at two of the urban sites in Long Island Sound and provide a framework for expanded studies to better define the extent and impact of chemical pollution in Long Island Sound.

  17. Fatal Caprine arthritis encephalitis virus-like infection in 4 Rocky Mountain goats (Oreamnos americanus).

    PubMed

    Patton, Kristin M; Bildfell, Robert J; Anderson, Mark L; Cebra, Christopher K; Valentine, Beth A

    2012-03-01

    Over a 3.5-year period, 4 Rocky Mountain goats (Oreamnos americanus), housed at a single facility, developed clinical disease attributed to infection by Caprine arthritis encephalitis virus (CAEV). Ages ranged from 1 to 10 years. Three of the goats, a 1-year-old female, a 2-year-old male, and a 5-year-old male, had been fed raw domestic goat milk from a single source that was later found to have CAEV on the premises. The fourth animal, a 10-year-old male, had not ingested domestic goat milk but had been housed with the other 3 Rocky Mountain goats. All 4 animals had clinical signs of pneumonia prior to death. At necropsy, findings in lungs included marked diffuse interstitial pneumonia characterized histologically by severe lymphoplasmacytic infiltrates with massive alveolar proteinosis, interstitial fibrosis, and type II pneumocyte hyperplasia. One animal also developed left-sided hemiparesis, and locally extensive lymphoplasmacytic myeloencephalitis was present in the cranial cervical spinal cord. Two animals had joint effusions, as well as severe lymphoplasmacytic and ulcerative synovitis. Immunohistochemical staining of fixed sections of lung tissue from all 4 goats, as well as spinal cord in 1 affected animal, and synovium from 2 affected animals were positive for CAEV antigen. Serology testing for anti-CAEV antibodies was positive in the 2 goats tested. The cases suggest that Rocky Mountain goats are susceptible to naturally occurring CAEV infection, that CAEV from domestic goats can be transmitted to this species through infected milk and by horizontal transmission, and that viral infection can result in clinically severe multisystemic disease.

  18. Multilocus heterozygosity, parental relatedness and individual fitness components in a wild mountain goat, Oreamnos americanus population.

    PubMed

    Mainguy, Julien; Côté, Steeve D; Coltman, David W

    2009-05-01

    Matings between relatives lead to a decrease in offspring genetic diversity which can reduce fitness, a phenomenon known as inbreeding depression. Because alpine ungulates generally live in small structured populations and often exhibit a polygynous mating system, they are susceptible to inbreeding. Here, we used marker-based measures of pairwise genetic relatedness and inbreeding to investigate the fitness consequences of matings between relatives in a long-term study population of mountain goats (Oreamnos americanus) at Caw Ridge, Alberta, Canada. We first assessed whether individuals avoided mating with kin by comparing actual and random mating pairs according to their estimated genetic relatedness, which was derived from 25 unlinked polymorphic microsatellite markers and reflected pedigree relatedness. We then examined whether individual multilocus heterozygosity H, used as a measure of inbreeding, was predicted by parental relatedness and associated with yearling survival and the annual probability of giving birth to a kid in adult females. Breeding pairs identified by genetic parentage analyses of offspring that survived to 1 year of age were less genetically related than expected under random matings. Parental relatedness was negatively correlated with offspring H, and more heterozygous yearlings had higher survival to 2 years of age. The probability of giving birth was not affected by H in adult females. Because kids that survived to yearling age were mainly produced by less genetically related parents, our results suggest that some individuals experienced inbreeding depression in early life. Future research will be required to quantify the levels of gene flow between different herds, and evaluate their effects on population genetic diversity and dynamics.

  19. Behavioral Thermoregulation and Trade-Offs in Juvenile Lobster Homarus americanus.

    PubMed

    Nielsen, Travis V; McGaw, Iain J

    2016-02-01

    Water temperature influences the behavior and distribution patterns of both larval and adult American lobster Homarus americanus. However, very little is known about the responses of juvenile lobsters. The juvenile life stage is a critical period; high levels of mortality, combined with specific behavioral responses, can disconnect larval settlement from patterns of abundance of adults. We assessed behavioral thermoregulation in juvenile lobsters, and determined how thermal preferences can be altered by the presence of shelter and food. Juvenile lobsters avoided temperatures higher than 20 °C and lower than 8 °C, and had a mean temperature preference of 16.2 ± 1 °C. This preference was unaffected by prior acclimation, origin (laboratory-raised or wild), or size. When the animals were subjected to a temperature change (5-20 °C), activity rates peaked at 15 °C, and remained stable thereafter. Activity rates did not change when a shelter was added. The addition of food resulted in an increase in activity associated with food handling. When juvenile lobsters were offered a choice between temperature, shelter, and food, they always chose the environment with a shelter, even when it was in a thermally unfavorable temperature. Juveniles also spent more time in a thermally unfavorable environment when food was present; however, acquisition of a shelter was prioritized over food. Although juveniles had a similar thermal preference to adults, they are more vulnerable to predation; the innate shelter-seeking behavior of juveniles overrode their thermal preference. While temperature is an important environmental factor affecting the physiology, distribution, and growth of aquatic ectotherms, our findings suggest that trade-off behaviors occur in order to maintain optimal fitness and survival of the individual. PMID:26896176

  20. Population trends and flight behavior of the American burying beetle, Nicrophorus americanus (Coleoptera: Silphidae), on Block Island, RI

    USGS Publications Warehouse

    Raithel, C.J.; Ginsberg, H.S.; Prospero, M.L.

    2006-01-01

    The endangered American burying beetle, Nicrophorus americanus, was monitored on Block Island, RI, USA, from 1991-2003 using mark-recapture population estimates of adults collected in pitfall traps. Populations increased through time, especially after 1994 when a program was initiated that provided carrion for beetle production. Beetle captures increased with increasing temperature and dew point, and decreased with increasing wind speed. Short distance movement was not related to wind direction, while longer distance flights tended to be downwind. Although many individuals flew considerable distances along transects, most recaptures were in traps near the point of release. These behaviors probably have counterbalancing effects on population estimates.

  1. Two species of commercial flatfish, winter flounder, Pleuronectes americanus, and American plaice, Hippoglossoides platessoides, as sentinels of environmental pollution.

    PubMed

    Khan, R A

    2010-08-01

    Two species of marketable-size flatfish, winter flounder (Pleuronectes americanus) and American plaice (Hippoglossoides platessoides) from a fjord, were examined as sentinels for the effects of effluent discharged by a pulp and paper mill in Newfoundland, Canada. Reference samples for comparison were obtained from a pristine fjord. Condition factor, lymphocyte levels and the abundance of two intestinal parasites were significantly greater in flounder and plaice sampled at the reference site while macroscopic and microscopic lesions, and hepatic somatic indices were greater in flatfish taken from the contaminated site. These results suggest that both species of commercial flatfish are useful as sentinels for studying environmental pollution.

  2. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (North Atlantic). American lobster. [Homarus americanus

    SciTech Connect

    MacKenzie, C.; Moring, J.R.

    1985-04-01

    This species profile is a literature summary of the taxonomy, morphology, distribution, life history, and environmental requirements of the American lobster (Homarus americanus). These species profiles are designed to assist in the preparation of environmental impact assessments. The American lobster is a valuable commercial shellfish. After spawning, lobsters undergo a series of molts; as adults they live in coastal and offshore waters. Lobsters are captured in baited traps and incidentally in trawls. About 5 to 6 million pounds were captured commercially in 1983, a downward trend from 1971. Major environmental factors affecting reproduction, growth, and survival are water temperature, oxygen concentration, salinity, and substrate. 82 refs., 2 figs., 3 tabs.

  3. Inter-animal variability in the effects of C-type allatostatin on the cardiac neuromuscular system in the lobster Homarus americanus

    PubMed Central

    Wiwatpanit, Teerawat; Powers, Brian; Dickinson, Patsy S.

    2012-01-01

    SUMMARY Although the global effects of many modulators on pattern generators are relatively consistent among preparations, modulators can induce different alterations in different preparations. We examined the mechanisms that underlie such variability in the modulatory effects of the peptide C-type allatostatin (C-AST; pQIRYHQCYFNPISCF) on the cardiac neuromuscular system of the lobster Homarus americanus. Perfusion of C-AST through the semi-intact heart consistently decreased the frequency of ongoing contractions. However, the effect of C-AST on contraction amplitude varied between preparations, decreasing in some preparations and increasing in others. To investigate this variable effect, we examined the effects of C-AST both peripherally and centrally. When contractions of the myocardium were elicited by controlled stimuli, C-AST did not alter heart contraction at the periphery (myocardium or neuromuscular junction) in any hearts. However, when applied either to the semi-intact heart or to the cardiac ganglion (CG) isolated from hearts that responded to C-AST with increased contraction force, C-AST increased both motor neuron burst duration and the number of spikes per burst by about 25%. In contrast, CG output was increased only marginally in hearts that responded to C-AST with a decrease in contraction amplitude, suggesting that the decrease in amplitude in those preparations resulted from decreased peripheral facilitation. Our data suggest that the differential effects of a single peptide on the cardiac neuromuscular system are due solely to differential effects of the peptide on the pattern generator; the extent to which the peptide induces increased burst duration is crucial in determining its overall effect on the system. PMID:22675192

  4. On neutral plasma oscillations

    SciTech Connect

    Shadwick, B.A.; Morrison, P.J.

    1993-06-01

    We examine the conditions for the existence of spectrally stable neutral modes in a Vlasov-Poisson plasma and show that for stable equilibria of systems that have unbounded spatial domain, the only possible neutral modes are those with phase velocities that correspond to stationary inflection points of the equilibrium distribution function. It is seen that these neutral modes can possess positive or negative free energy.

  5. Human Papillomavirus neutralizing and cross-reactive antibodies induced in HIV-positive subjects after vaccination with quadrivalent and bivalent HPV vaccines.

    PubMed

    Faust, Helena; Toft, Lars; Sehr, Peter; Müller, Martin; Bonde, Jesper; Forslund, Ola; Østergaard, Lars; Tolstrup, Martin; Dillner, Joakim

    2016-03-18

    Ninety-one HIV-infected individuals (61 men and 30 women) were randomized to vaccination either with quadrivalent (Gardasil™) or bivalent (Cervarix™) HPV vaccine. Neutralizing and specific HPV-binding serum antibodies were measured at baseline and 12 months after the first vaccine dose. Presence of neutralizing and binding antibodies had good agreement (average Kappa for HPV types 6, 11, 16, 18, 31, 33 and 45 was 0.65). At baseline, 88% of subjects had antibodies against at least one genital HPV. Following vaccination with Cervarix™, all subjects became seropositive for HPV16 and 18. After Gardasil™ vaccination, 96% of subjects seroconverted for HPV16 and 73% for HPV18. Levels of HPV16-specific antibodies were <1 international unit (IU) in 87% of study subjects before vaccination but >10IU in 85% of study subjects after vaccination. Antibodies against non-vaccine HPV types appeared after Gardasil™ vaccination for >50% of vaccinated females for HPV 31, 35 and 73 and for >50% of Cervarix™-vaccinated females for HPV 31, 33, 35, 45, 56 and 58. Cross-reactivity with non-genital HPV types was also detected. In conclusion, HIV-infected subjects responded to HPV vaccination with induction of neutralizing antibodies against both vaccine and non-vaccine types.

  6. Human Rhinovirus Type 14:Human Immunodeficiency Virus Type 1 (HIV-1) V3 Loop Chimeras from a Combinatorial Library Induce Potent Neutralizing Antibody Responses against HIV-1

    PubMed Central

    Smith, Allen D.; Geisler, Sheila C.; Chen, Anne A.; Resnick, Dawn A.; Roy, Birgit M.; Lewi, Paul J.; Arnold, Edward; Arnold, Gail Ferstandig

    1998-01-01

    In an effort to develop a useful AIDS vaccine or vaccine component, we have generated a combinatorial library of chimeric viruses in which the sequence IGPGRAFYTTKN from the V3 loop of the MN strain of human immunodeficiency virus type 1 (HIV-1) is displayed in many conformations on the surface of human rhinovirus 14 (HRV14). The V3 loop sequence was inserted into a naturally immunogenic site of the cold-causing HRV14, bridged by linkers consisting of zero to three randomized amino acids on each side. The library of chimeric viruses obtained was subjected to a variety of immunoselection schemes to isolate viruses that provided the most useful presentations of the V3 loop sequence for potential use in a vaccine against HIV. The utility of the presentations was assessed by measures of antigenicity and immunogenicity. Most of the immunoselected chimeras examined were potently neutralized by each of the four different monoclonal anti-V3 loop antibodies tested. Seven of eight chimeric viruses were able to elicit neutralizing antibody responses in guinea pigs against the MN and ALA-1 strains of HIV-1. Three of the chimeras elicited HIV neutralization titers that exceeded those of all but a small number of previously described HIV immunogens. These results indicate that HRV14:HIV-1 chimeras may serve as useful immunogens for stimulating immunity against HIV-1. This method can be used to flexibly reconstruct varied immunogens on the surface of a safe and immunogenic vaccine vehicle. PMID:9420270

  7. ALEX neutral beam probe

    SciTech Connect

    Pourrezaei, K.

    1982-01-01

    A neutral beam probe capable of measuring plasma space potential in a fully 3-dimensional magnetic field geometry has been developed. This neutral beam was successfully used to measure an arc target plasma contained within the ALEX baseball magnetic coil. A computer simulation of the experiment was performed to refine the experimental design and to develop a numerical model for scaling the ALEX neutral beam probe to other cases of fully 3-dimensional magnetic field. Based on this scaling a 30 to 50 keV neutral cesium beam probe capable of measuring space potential in the thermal barrier region of TMX Upgrade was designed.

  8. Search for neutral leptons

    SciTech Connect

    Perl, M.L.

    1984-12-01

    At present we know of three kinds of neutral leptons: the electron neutrino, the muon neutrino, and the tau neutrino. This paper reviews the search for additional neutral leptons. The method and significance of a search depends upon the model used for the neutral lepton being sought. Some models for the properties and decay modes of proposed neutral leptons are described. Past and present searches are reviewed. The limits obtained by some completed searches are given, and the methods of searches in progress are described. Future searches are discussed. 41 references.

  9. The effects of ambient pH on nitrogen excretion in early life stages of the American toad (Bufo americanus).

    PubMed

    Tattersall, G J; Wright, P A

    1996-04-01

    Acidification of breeding ponds has been identified as a potential threat to the survival and health of North American amphibian populations. The effects of acid exposure on ion and acid-balance are well known, but there is little information on how environmental water pH influences nitrogen balance in amphibians. The aim of this study was to determine the effects of moderately acidic water (pH 6.0) on nitrogen excretion in early life stages of the toad, Bufo americanus. Acid exposure (pH 6.0, 54 h) resulted in a 20-80% increase in ammonia-N excretion rates in embryos and early, middle and late tadpoles stages, whereas there was no significant effect on urea-N excretion. Tissue ammonia concentrations were significantly higher (+33%) in the embryos and 35-65% lower in the three groups of tadpoles exposed to water of pH 6.0 compared to control animals (pH 8.5). In embryos, ammonia excretion accounted for greater than 90% of total nitrogen excretion (ammonia-N + urea-N), but by the late tadpole stage this value had decreased to approximately 65%. These findings indicate that exposure of embryonic and larval B. americanus to moderately acidic water disrupts nitrogen balance by increasing nitrogen loss as ammonia, with no compensatory decrease in urea excretion.

  10. Manganese concentration in lobster (Homarus americanus) gills as an index of exposure to reducing conditions in western Long Island Sound

    USGS Publications Warehouse

    Draxler, Andrew F.J.; Sherrell, Robert M.; Wieczorek, Dan; Lavigne, Michele G.; Paulson, A.J.

    2005-01-01

    We examined the accumulation of manganese (Mn) in gill tissues of chemically nai??ve lobsters held in situ at six sites in Long Island Sound (LIS) for up to six weeks to evaluate the possible contribution of eutrophication-driven habitat quality factors to the 1999 mass mortality of American lobsters (Homarus americanus). These western LIS lobster habitats experience seasonal hypoxia, which results in redox-mobilized Mn being transferred to and deposited on the tissues of the lobsters. Manganese accumulated in gill tissue of lobsters throughout the study, but rates were highest at western and southern LIS sites, ranging from 3.4-0.8 ??g/g/d (???16 ??g/g initial). The Baden-Eriksson observation that Mn accumulation in Norway lobsters (Nephrops norvegicus) is associated with ecosystem hypoxia is confirmed and extended to H. americanus. It seems likely that, after accounting for molting frequency, certain critical values may be applied to other lobster habitats of the NE US shelf. If a high proportion of lobsters in autumn have gill Mn concentrations exceeding 30 ??g/g, then the habitats are likely experiencing some reduced oxygen levels. Manganese concentrations above 100 ??g/g suggest exposure to conditions with the potential for lobster mortality should the temperatures of bottom waters become elevated, and gill concentrations above some higher level (perhaps 300 ??g/g) indicate the most severe habitat conditions with a strong potential for hypoxia stress.

  11. Evaluation of smallpox vaccines using variola neutralization.

    PubMed

    Damon, Inger K; Davidson, Whitni B; Hughes, Christine M; Olson, Victoria A; Smith, Scott K; Holman, Robert C; Frey, Sharon E; Newman, Frances; Belshe, Robert B; Yan, Lihan; Karem, Kevin

    2009-08-01

    The search for a 'third'-generation smallpox vaccine has resulted in the development and characterization of several vaccine candidates. A significant barrier to acceptance is the absence of challenge models showing induction of correlates of protective immunity against variola virus. In this light, virus neutralization provides one of few experimental methods to show specific 'in vitro' activity of vaccines against variola virus. Here, we provide characterization of the ability of a modified vaccinia virus Ankara vaccine to induce variola virus-neutralizing antibodies, and we provide comparison with the neutralization elicited by standard Dryvax vaccination.

  12. Seasonal changes in spermatogenesis and testicular steroidogenesis in the male black bear Ursus americanus.

    PubMed

    Tsubota, T; Howell-Skalla, L; Nitta, H; Osawa, Y; Mason, J I; Meiers, P G; Nelson, R A; Bahr, J M

    1997-01-01

    American black bears, Ursus americanus, are seasonal breeders with a mating season in late spring to early summer. The objectives of this study were to determine whether there are seasonal changes in spermatogenesis and immunolocalization of testicular steroidogenic enzymes, and to correlate these changes with peripheral steroid concentrations. Three captive mature bears were maintained in open cages during the summer season and provided with chambers for denning during the winter. Testicular biopsies and blood samples were obtained from anaesthetized bears on 12 March, 15 June, 12 October and 15 January. Steroidogenic enzymes were immunolocalized using polyclonal antisera raised against bovine adrenal cholesterol side-chain cleavage cytochrome P450 (P450scc), human placental 3 beta-hydroxysteroid dehydrogenase (3 beta HSD), porcine testicular 17 alpha-hydroxylase cytochrome P450 (P450c17) and human placental aromatase cytochrome P450 (P450arom). Spermatogenesis changed seasonally: spermatogonia and degenerating spermatocytes were observed in October; spermatogonia and primary spermatocytes were present in January; spermatogonia, spermatocytes and round spermatids were present in March; and spermatogonia through spermatozoa were present in June. P450scc and P450c17 were immunolocalized in spermatids and Leydig cells in June, whereas in October these enzymes were present only in Leydig cells. 3 beta HSD was localized in Leydig cells in June and October with more intense staining in June. Localization of P450arom changed seasonally: no immunostaining in October; positive immunostaining in Sertoli cells in January; more extensive immunostaining in Sertoli cells, peritubular-myoid cells and round spermatids in March; and strong immunostaining in Sertoli cells and round and elongating spermatids in June. Serum testosterone and oestradiol concentrations changed seasonally: testosterone and oestrogen were low in October and January, slightly higher in March, and high in

  13. Neutrality in Language Policy

    ERIC Educational Resources Information Center

    Wee, Lionel

    2010-01-01

    The unavoidability of language makes it critical that language policies appeal to some notion of language neutrality as part of their rationale, in order to assuage concerns that the policies might otherwise be unduly discriminatory. However, the idea of language neutrality is deeply ideological in nature, since it is not only an attempt to treat…

  14. Context matters: The importance of dimerization-induced conformation of the LukGH leukocidin of Staphylococcus aureus for the generation of neutralizing antibodies

    PubMed Central

    Badarau, Adriana; Rouha, Harald; Malafa, Stefan; Battles, Michael B.; Walker, Laura; Nielson, Nels; Dolezilkova, Ivana; Teubenbacher, Astrid; Banerjee, Srijib; Maierhofer, Barbara; Weber, Susanne; Stulik, Lukas; Logan, Derek T.; Welin, Martin; Mirkina, Irina; Pleban, Clara; Zauner, Gerhild; Gross, Karin; Jägerhofer, Michaela; Magyarics, Zoltán; Nagy, Eszter

    2016-01-01

    ABSTRACT LukGH (LukAB) is a potent leukocidin of Staphylococcus aureus that lyses human phagocytic cells and is thought to contribute to immune evasion. Unlike the other bi-component leukocidins of S. aureus, LukGH forms a heterodimer before binding to its receptor, CD11b expressed on professional phagocytic cells, and displays significant sequence variation. We employed a high diversity human IgG1 library presented on yeast cells to discover monoclonal antibodies (mAbs) neutralizing the cytolytic activity of LukGH. Recombinant LukG and LukH monomers or a LukGH dimer were used as capture antigens in the library selections. We found that mAbs identified with LukG or LukH as bait had no or very low toxin neutralization potency. In contrast, LukGH dimer-selected antibodies proved to be highly potent, and several mAbs were able to neutralize even the most divergent LukGH variants. Based on biolayer interferometry and mesoscale discovery, the high affinity antibody binding site on the LukGH complex was absent on the individual monomers, suggesting that it was generated upon formation of the LukG-LukH dimer. X-ray crystallography analysis of the complex between the LukGH dimer and the antigen-binding fragment of a very potent mAb (PDB code 5K59) indicated that the epitope is located in the predicted cell binding region (rim domain) of LukGH. The corresponding IgG inhibited the binding of LukGH dimer to target cells. Our data suggest that knowledge of the native conformation of target molecules is essential to generate high affinity and functional mAbs. PMID:27467113

  15. Neutralization of nerve growth factor induces plasticity of ATP-sensitive P2X3 receptors of nociceptive trigeminal ganglion neurons.

    PubMed

    D'Arco, Marianna; Giniatullin, Rashid; Simonetti, Manuela; Fabbro, Alessandra; Nair, Asha; Nistri, Andrea; Fabbretti, Elsa

    2007-08-01

    The molecular mechanisms of migraine pain are incompletely understood, although migraine mediators such as NGF and calcitonin gene-related peptide (CGRP) are believed to play an algogenic role. Although NGF block is proposed as a novel analgesic approach, its consequences on nociceptive purinergic P2X receptors of trigeminal ganglion neurons remain unknown. We investigated whether neutralizing NGF might change the function of P2X3 receptors natively coexpressed with NGF receptors on cultured mouse trigeminal neurons. Treatment with an NGF antibody (24 h) decreased P2X3 receptor-mediated currents and Ca2+ transients, an effect opposite to exogenously applied NGF. Recovery from receptor desensitization was delayed by anti-NGF treatment without changing desensitization onset. NGF neutralization was associated with decreased threonine phosphorylation of P2X3 subunits, presumably accounting for their reduced responses and slower recovery. Anti-NGF treatment could also increase the residual current typical of heteromeric P2X2/3 receptors, consistent with enhanced membrane location of P2X2 subunits. This possibility was confirmed with cross-linking and immunoprecipitation studies. NGF neutralization also led to increased P2X2e splicing variant at mRNA and membrane protein levels. These data suggest that NGF controlled plasticity of P2X3 subunits and their membrane assembly with P2X2 subunits. Despite anti-NGF treatment, CGRP could still enhance P2X3 receptor activity, indicating separate NGF- or CGRP-mediated mechanisms to upregulate P2X3 receptors. In an in vivo model of mouse trigeminal pain, anti-NGF pretreatment suppressed responses evoked by P2X3 receptor activation. Our findings outline the important contribution by NGF signaling to nociception of trigeminal sensory neurons, which could be counteracted by anti-NGF pretreatment.

  16. Sequential developmental acquisition of cotransmitters in identified sensory neurons of the stomatogastric nervous system of the lobsters, Homarus americanus and Homarus gammarus.

    PubMed

    Kilman, V; Fénelon, V S; Richards, K S; Thirumalai, V; Meyrand, P; Marder, E

    1999-06-01

    We studied the developmental acquisition of three of the cotransmitters found in the gastropyloric receptor (GPR) neurons of the stomatogastric nervous systems of the lobsters Homarus americanus and Homarus gammarus. By using wholemount immunocytochemistry and confocal microscopy, we examined the distribution of serotonin-like, allatostatin-like, and FLRF(NH2)-like immunoreactivities within the stomatogastric nervous system of embryonic, larval, juvenile, and adult animals. The GPR neurons are peripheral sensory neurons that send proprioceptive information to the stomatogastric and commissural ganglia. In H. americanus, GPR neurons of the adult contain serotonin-like, allatostatin-like, and Phe-Leu-Arg-Phe-amide (FLRF(NH2))-like immunoreactivities. In the stomatogastric ganglion (STG) of the adult H. americanus and H. gammarus, all of the serotonin-like and allatostatin-like immunoreactivity colocalizes in neuropil processes that are derived exclusively from ramifications of the GPR neurons. In both species, FLRF(NH2)-like immunoreactivity was detected in the STG neuropil by 50% of embryonic development (E50). Allatostatin-like immunoreactivity was visible first in the STG at approximately E70-E80. In contrast, serotonin staining was not clearly visible until larval stage I (LI) in H. gammarus and until LII or LIII in H. americanus. These data indicate that there is a sequential acquisition of the cotransmitters of the GPR neurons. PMID:10340509

  17. ISOLATION AND GENETIC CHARACTERIZATION OF TOXOPLASMA GONDII FROM RACCOONS (PROCYON LOTOR), CATS (FELIS DOMESTICUS), STRIPED SKUNK (MEPHITIS MEPHITIS), BLACK BEAR (URSUS AMERICANUS), AND COUGAR (PUMA CONCOLOR) FROM CANADA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats ( Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus ) from Kuujjuaq, northern Quebec, Canada. Geno...

  18. The influence of stray magnetic fields on ion beam neutralization

    NASA Technical Reports Server (NTRS)

    Feng, Y.-C.; Wilbur, P. J.

    1982-01-01

    An experimental investigation is described of a comparison between the ion beam neutralization characteristics of a local neutralizer (within approximately 5 cm of the beam edge) and those associated with a distant one (approximately 1 meter away from the thruster). The influence of magnetic fields in the vicinity of the neutralizer cathode orifice which are either parallel or normal to the neutralizer axis is assessed. The plasma property profiles which reflect the influence of the magnetic fields are measured. The results suggest that magnetic fields at the region of a neutralizer cathode orifice influence its ability to couple to the ion beam. They reveal that there is a potential jump from the neutralizer cathode orifice to the plasma which exists close to the orifice. This potential drop is found to increase as the axial component of magnetic flux density increases. A magnetic field perpendicular to the neutralizer axis induces a potential rise a few centimeters downstream from the neutralizer cathode.

  19. Interferon α kinoid induces neutralizing anti-interferon α antibodies that decrease the expression of interferon-induced and B cell activation associated transcripts: analysis of extended follow-up data from the interferon α kinoid phase I/II study

    PubMed Central

    Ducreux, Julie; Houssiau, Frédéric A.; Vandepapelière, Pierre; Jorgensen, Christian; Lazaro, Estibaliz; Spertini, François; Colaone, Fabien; Roucairol, Camille; Laborie, Marion; Croughs, Thérèse; Lauwerys, Bernard R.

    2016-01-01

    Objective. IFN α Kinoid (IFN-K) is a therapeutic vaccine composed of IFNα2b coupled to a carrier protein. In a phase I/II placebo-controlled trial, we observed that IFN-K significantly decreases the IFN gene signature in whole blood RNA samples from SLE patients. Here, we analysed extended follow-up data from IFN-K-treated patients, in order to evaluate persistence of neutralizing anti-IFNα Abs antibodies (Abs), and gene expression profiling. Methods. Serum and whole blood RNA samples were obtained in IFN-K-treated patients included in the follow-up study, in order to determine binding and neutralizing anti-IFNα Ab titres, and perform high-throughput transcriptomic studies. Results. Neutralization studies of 13 IFNα subtypes demonstrated the polyclonal nature of the Ab response induced by IFN-K. Follow-up analyses in six patients confirmed a significant correlation between neutralizing anti-IFNα Ab titres and decrease in IFN scores compared to baseline. These analyses also revealed an inhibitory effect of IFNα blockade on the expression of B cell associated transcripts. Conclusions. IFN-K induces a polyclonal anti-IFNα response that decreases IFN- and B cell-associated transcripts. Trial registration: ClinicalTrials.gov, clinicaltrials.gov, NCT01058343 PMID:27354683

  20. Space station neutral external environment

    NASA Technical Reports Server (NTRS)

    Ehlers, H.; Leger, L.

    1988-01-01

    Molecular contamination levels arising from the external induced neutral environment of the Space Station (Phase 1 configuration) were calculated using the MOLFLUX model. Predicted molecular column densities and deposition rates generally meet the Space Station contamination requirements. In the doubtful cases of deposition due to materials outgassing, proper material selection, generally excluding organic products exposed to the external environment, must be considered to meet contamination requirements. It is important that the Space Station configuration, once defined, is not significantly modified to avoid introducing new unacceptable contamination sources.

  1. Human Immunodeficiency Virus Type 1 Escape from Cyclotriazadisulfonamide-Induced CD4-Targeted Entry Inhibition Is Associated with Increased Neutralizing Antibody Susceptibility▿

    PubMed Central

    Vermeire, Kurt; Van Laethem, Kristel; Janssens, Wouter; Bell, Thomas W.; Schols, Dominique

    2009-01-01

    Continuous specific downmodulation of CD4 receptor expression in T lymphocytes by the small molecule cyclotriazadisulfonamide (CADA) selected for the CADA-resistant human immunodeficiency virus type 1 (HIV-1) NL4.3 virus containing unique mutations in the C4 and V5 regions of gp120, likely stabilizing the CD4-binding conformation. The amino acid changes in Env were associated with decreased susceptibility to anti-CD4 monoclonal antibody treatment of the cells and with higher susceptibility of the virus to soluble CD4. In addition, the acquired ability of a CADA-resistant virus to infect cells with low CD4 expression was associated with an increased susceptibility of the virus to neutralizing antibodies from sera of several HIV-1-infected patients. PMID:19570853

  2. Neutralization Assay for Chikungunya Virus Infection: Plaque Reduction Neutralization Test.

    PubMed

    Azami, Nor Azila Muhammad; Moi, Meng Ling; Takasaki, Tomohiko

    2016-01-01

    Neutralization assay is a technique that detects and quantifies neutralizing antibody in serum samples by calculating the percentage of reduction of virus activity, as the concentration of virus used is usually constant. Neutralizing antibody titer is conventionally determined by calculating the percentage reduction in total virus infectivity by counting and comparing number of plaques (localized area of infection due to cytopathic effect) with a standard amount of virus. Conventional neutralizing test uses plaque-reduction neutralization test (PRNT) to determine neutralizing antibody titers against Chikungunya virus (CHIKV). Here we describe the plaque reduction neutralization assay (PRNT) using Vero cell lines to obtain neutralizing antibody titers.

  3. Solar Neutral Particles

    NASA Video Gallery

    This animation shows a neutral solar particle's path leaving the sun, following the magnetic field lines out to the heliosheath. The solar particle hits a hydrogen atom, stealing its electron, and ...

  4. Serologic Survey of Snowshoe Hares (Lepus americanus) in the Greater Yellowstone Area for Brucellosis, Tularemia, and Snowshoe Hare Virus.

    PubMed

    Tyers, Dan; Zimmer, Jeremy; Lewandowski, Kristen; Hennager, Steve; Young, John; Pappert, Ryan; Panella, Amanda; Kosoy, Olga

    2015-07-01

    We examined sera from snowshoe hares (Lepus americanus) livetrapped in the northern Greater Yellowstone Area (GYA), US, for antibodies to Brucella abortus, Francisella tularensis, and snowshoe hare virus (SSHV). Zero of 90, 0 of 67, and 40 of 100 samples were antibody positive for B. abortus, F. tularensis, and SSHV, respectively. Hares were trapped from 2009 to 2012, and of the six animals that were captured twice with at least 1 yr between captures, four developed antibody to SSHV, indicating active exposure to the agent. These findings suggest snowshoe hares in the GYA do not play a significant role as a reservoir of B. abortus, but do maintain the zoonotic, encephalitic SSHV in the population.

  5. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus)

    PubMed Central

    Nelson, Danielle D.; Duprau, Jennifer L.; Wolff, Peregrine L.; Evermann, James F.

    2016-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus). PMID:26779126

  6. Investigation of American lobster, Homarus americanus, for the presence of chlorinated dibenzo-rho-dioxins and dibenzofurans

    SciTech Connect

    Clement, R.E.; Tosine, H.M.; Taguchi, V.; Musial, C.J.; Uthe, J.F.

    1987-12-01

    The polychlorinated dibenzo-p-dioxins (PCDD) are a group of 75 compounds of current environmental concern. Most attention has been focused on the 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8,-TCDD) because of high toxicity exhibited in laboratory animal studies. Polychlorinated dibenzofurans (PCDF) comprise 135 compounds similar to the PCDD in structure and toxicity. The 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) is the most toxic of this group. Two principal sources of PCDD and PCDF in the environment are incineration and as by-products in the manufacture and use of pentachlorophenols. American lobsters (Homarus americanus) have not been previously investigated for the presence of PCDD and PCDF. Lobsters were examined in this study because of their proximity to possible sources of PCDD and PCDF and an ability to concentrate hydrophobic organics such as polycyclic aromatic hydrocarbons (PAH) in the digestive gland.

  7. Cadmium contamination in American lobster, Homarus americanus, near a coastal lead smelter: use of multiple linear regression for management

    SciTech Connect

    Uthe, J.F.; Scott, D.P.; Chou, C.L.

    1987-04-01

    In 1980 cadmium (Cd) concentrations in digestive gland from American Lobster (Homarus americanus), captured at Belledune Harbour, New Brunswick, Canada were found to range 47.6-372 mg/kg wet weight. Since the digestive gland is commonly eaten the harbor fishery was closed. The adjacent area was decreed a controlled fishery zone. The cadmium source was a lead smelter on the harbor shore. The company installed an aqueous effluent treatment plant and improved handling procedures within the plant area. Aqueous Cd discharges were subsequently reduced by more than 95%. Cadmium levels in lobsters have been monitored annually since 1980 by sampling in early spring, immediately after the lobsters emerged from their overwintering locations. The results from the 1981-1985 monitoring program were used to model the system, analyze the data and predict the years in which certain changes to the management plan might be implemented.

  8. Serologic survey of Toxoplasma gondii in grizzly bears (Ursus arctos) and black bears (Ursus americanus), from Alaska, 1988 to 1991.

    PubMed

    Chomel, B B; Zarnke, R L; Kasten, R W; Kass, P H; Mendes, E

    1995-10-01

    We tested 644 serum samples from 480 grizzly bears and 40 black bears from Alaska (USA), collected between 1988 and 1991, for Toxoplasma gondii antibodies, using a commercially available latex agglutination test (LAT). A titer > or = 64 was considered positive. Serum antibody prevalence for T. gondii in grizzly bears (Ursus arctos) was 18% (87 of 480). Prevalence ranged from 9% (seven of 77) on Kodiak Island to 28% (15 of 54) in northern Alaska. Prevalence was directly correlated to age. No grizzly bears < 2-year-old had T. gondii antibody. High antibody titers were found mainly in grizzly bears captured north of the Arctic Circle. Antibody prevalence in black bears (Ursus americanus) from Interior Alaska was 15% (six of 40), similar to the prevalence in grizzly bears from the same area (13%; five of 40).

  9. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Duprau, Jennifer L; Wolff, Peregrine L; Evermann, James F

    2015-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus).

  10. Serologic Survey of Snowshoe Hares (Lepus americanus) in the Greater Yellowstone Area for Brucellosis, Tularemia, and Snowshoe Hare Virus.

    PubMed

    Tyers, Dan; Zimmer, Jeremy; Lewandowski, Kristen; Hennager, Steve; Young, John; Pappert, Ryan; Panella, Amanda; Kosoy, Olga

    2015-07-01

    We examined sera from snowshoe hares (Lepus americanus) livetrapped in the northern Greater Yellowstone Area (GYA), US, for antibodies to Brucella abortus, Francisella tularensis, and snowshoe hare virus (SSHV). Zero of 90, 0 of 67, and 40 of 100 samples were antibody positive for B. abortus, F. tularensis, and SSHV, respectively. Hares were trapped from 2009 to 2012, and of the six animals that were captured twice with at least 1 yr between captures, four developed antibody to SSHV, indicating active exposure to the agent. These findings suggest snowshoe hares in the GYA do not play a significant role as a reservoir of B. abortus, but do maintain the zoonotic, encephalitic SSHV in the population. PMID:26161724

  11. Persistent Bovine Viral Diarrhea Virus Infection in Domestic and Wild Small Ruminants and Camelids Including the Mountain Goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Duprau, Jennifer L; Wolff, Peregrine L; Evermann, James F

    2015-01-01

    Bovine viral diarrhea virus (BVDV) is a pestivirus best known for causing a variety of disease syndromes in cattle, including gastrointestinal disease, reproductive insufficiency, immunosuppression, mucosal disease, and hemorrhagic syndrome. The virus can be spread by transiently infected individuals and by persistently infected animals that may be asymptomatic while shedding large amounts of virus throughout their lifetime. BVDV has been reported in over 40 domestic and free-ranging species, and persistent infection has been described in eight of those species: white-tailed deer, mule deer, eland, mousedeer, mountain goats, alpacas, sheep, and domestic swine. This paper reviews the various aspects of BVDV transmission, disease syndromes, diagnosis, control, and prevention, as well as examines BVDV infection in domestic and wild small ruminants and camelids including mountain goats (Oreamnos americanus). PMID:26779126

  12. Effects of Multiple Routes of Cadmium Exposure on the Hibernation Success of the American Toad (Bufo americanus)

    USGS Publications Warehouse

    James, S.M.; Little, E.E.; Semlitsch, R.D.

    2004-01-01

    The effects of multiple routes of cadmium exposure on juvenile American toads (Bufo americanus) were evaluated using environmentally relevant concentrations. During or after exposure, toads were individually hibernated for 172 days at approximately 4??C. The following experiments were conducted: (1) dermal exposure (hibernation in soil contaminated with up to 120 ??g Cd/ g (dry weight)); (2) injection exposure (single injection with cadmium to achieve a maximum whole-body nominal concentration of 3 ??g Cd/g (wet weight) 12 days before hibernation in uncontaminated soil); and, (3) oral exposure (feeding with mealworms containing ???16 ??g Cd/g (dry weight) for 50 days before hibernation in uncontaminated soil)., We hypothesized that sublethal levels of cadmium would become lethal during hibernation because of combined chemical and cold stress. No prehibernation mortality occurred in the injection and oral exposure studies. There was a significant treatment effect on whole-body cadmium concentration in toads orally or dermally exposed and on percent of cadmium retention in toads orally exposed. There was also a trend of increased time-to-burrowing and more toads partially buried with greater cadmium concentration in the dermal study, which indicated avoidance. In all 3 experiments, no significant differences were found among cadmium treatments in hibernation survival, percent of mass loss, or locomotor performance. However, toads fed mealworms averaging 4.7 ??g Cd/g (dry weight) had only 56% survival compared with 100% survival for controls. Although our results suggest that environmentally relevant levels of cadmium do not pose a great risk to American toads, factors such as soil type or prey species may increase cadmium bioavailability, and other amphibian species may be more sensitive to cadmium than B. americanus.

  13. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    PubMed

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species. PMID:25989983

  14. Phylogeographic Analyses of American Black Bears (Ursus americanus) Suggest Four Glacial Refugia and Complex Patterns of Postglacial Admixture.

    PubMed

    Puckett, Emily E; Etter, Paul D; Johnson, Eric A; Eggert, Lori S

    2015-09-01

    Studies of species with continental distributions continue to identify intraspecific lineages despite continuous habitat. Lineages may form due to isolation by distance, adaptation, divergence across barriers, or genetic drift following range expansion. We investigated lineage diversification and admixture within American black bears (Ursus americanus) across their range using 22 k single nucleotide polymorphisms and mitochondrial DNA sequences. We identified three subcontinental nuclear clusters which we further divided into nine geographic regions: Alaskan (Alaska-East), eastern (Central Interior Highlands, Great Lakes, Northeast, Southeast), and western (Alaska-West, West, Pacific Coast, Southwest). We estimated that the western cluster diverged 67 ka, before eastern and Alaskan divergence 31 ka; these divergence dates contrasted with those from the mitochondrial genome where clades A and B diverged 1.07 Ma, and clades A-east and A-west diverged 169 ka. We combined estimates of divergence timing with hindcast species distribution models to infer glacial refugia for the species in Beringia, Pacific Northwest, Southwest, and Southeast. Our results show a complex arrangement of admixture due to expansion out of multiple refugia. The delineation of the genomic population clusters was inconsistent with the ranges for 16 previously described subspecies. Ranges for U. a. pugnax and U. a. cinnamomum were concordant with admixed clusters, calling into question how to order taxa below the species level. Additionally, our finding that U. a. floridanus has not diverged from U. a. americanus also suggests that morphology and genetics should be reanalyzed to assess taxonomic designations relevant to the conservation management of the species.

  15. Radiation-induced DNA double-strand breaks produced in histone-depleted tumor cell nuclei measured using the neutral comet assay

    SciTech Connect

    Olive, P.L.; Banath, J.P.

    1995-05-01

    Removal of histones and other nuclear proteins greatly enhances the sensitivity of mammalian cells to DNA damage by ionizing radiation. We examined the possibility that the ease of dissociation of histones, or the association of other nuclear proteins with DNA, may differ between radioresistant and sensitive human tumor cells. Cells embedded in agarose were exposed to increasing salt concentrations prior to irradiation and examination using a microscopic gel electrophoresis method, the neutral comet assay. Induction of double-strand breaks increased by a factor of about 20 when cells of four human tumor cell line HT144 melanoma, HT29 adenocarcinoma, DU145 prostate carcinoma and U87 glioma, were exposed to 2 M NaCl; however, no correlation with radiosensitivity was apparent. While a significant number of histone and non-histone proteins are present after extraction with 1.2 M NaCL, these proteins apparently have only a minor influence on radiosensitivity. However, if they are allowed to remain with DNA during electrophoresis, about 15 times more strand breaks are required to produce a similar amount of DNA migration in both DU145 and HT144 cells. These results suggest that the association between proteins and DNA within the nucleus, as probed by extraction with sodium chloride, does not help to explain differences in intrinsic radiosensitivity among cells of these diverse tumor cell lines. 33 refs., 11 figs.

  16. On the influence of a Rashba-type coupling induced by Lorentz-violating effects on a Landau system for a neutral particle

    SciTech Connect

    Bakke, K.; Belich, H.

    2015-03-15

    We study a possible scenario of the Lorentz symmetry violation background that allows us to build an analogue of the Landau system for a nonrelativistic Dirac neutral particle interacting with a field configuration of crossed electric and magnetic fields. We also discuss the arising of analogues of the Rashba coupling, the Zeeman term and the Darwin term from the Lorentz symmetry breaking effects, and the influence of these terms on the analogue of the Landau system confined to a two-dimensional quantum ring. Finally, we show that this analogy with the Landau system confined to a two-dimensional quantum ring allows us to establish an upper bound for the Lorentz symmetry breaking parameters. - Highlights: • Landau system from crossed electric and magnetic fields and fixed time-like vector. • Analogues of the Rashba coupling, the Zeeman term and the Darwin term. • Lorentz symmetry breaking effects on a two-dimensional quantum ring. • Upper bound for the Lorentz symmetry breaking parameters.

  17. Multimeric Scaffolds Displaying the HIV-1 Envelope MPER Induce MPER-Specific Antibodies and Cross-Neutralizing Antibodies when Co-Immunized with gp160 DNA

    PubMed Central

    Krebs, Shelly J.; McBurney, Sean P.; Kovarik, Dina N.; Waddell, Chelsea D.; Jaworski, J. Pablo; Sutton, William F.; Gomes, Michelle M.; Trovato, Maria; Waagmeester, Garret; Barnett, Susan J.; DeBerardinis, Piergiuseppe; Haigwood, Nancy L.

    2014-01-01

    Developing a vaccine that overcomes the diversity of HIV-1 is likely to require a strategy that directs antibody (Ab) responses toward conserved regions of the viral Envelope (Env). However, the generation of neutralizing Abs (NAbs) targeting these regions through vaccination has proven to be difficult. One conserved region of particular interest is the membrane proximal external region (MPER) of Env located within the gp41 ectodomain. In order to direct the immune response to this region, the MPER and gp41 ectodomain were expressed separately as N-terminal fusions to the E2 protein of Geobacillus stearothermophilus. The E2 protein acts as a scaffold by self-assembling into 60-mer particles, displaying up to 60 copies of the fused target on the surface. Rabbits were immunized with E2 particles displaying MPER and/or the gp41 ectodomain in conjunction with DNA encoding full-length gp160. Only vaccines including E2 particles displaying MPER elicited MPER-specific Ab responses. NAbs were elicited after two immunizations that largely targeted the V3 loop. To overcome V3 immunodominance in the DNA component, E2 particles displaying MPER were used in conjunction with gp160 DNA lacking hypervariable regions V2, V3, or combined V1V2V3. All rabbits had HIV binding Ab responses and NAbs following the second vaccination. Using HIV-2/HIV-1 MPER chimeric viruses as targets, NAbs were detected in 12/16 rabbits after three immunizations. Low levels of NAbs specific for Tier 1 and 2 viruses were observed in all groups. This study provides evidence that co-immunizing E2 particles displaying MPER and gp160 DNA can focus Ab responses toward conserved regions of Env. PMID:25514675

  18. Multimeric scaffolds displaying the HIV-1 envelope MPER induce MPER-specific antibodies and cross-neutralizing antibodies when co-immunized with gp160 DNA.

    PubMed

    Krebs, Shelly J; McBurney, Sean P; Kovarik, Dina N; Waddell, Chelsea D; Jaworski, J Pablo; Sutton, William F; Gomes, Michelle M; Trovato, Maria; Waagmeester, Garret; Barnett, Susan J; DeBerardinis, Piergiuseppe; Haigwood, Nancy L

    2014-01-01

    Developing a vaccine that overcomes the diversity of HIV-1 is likely to require a strategy that directs antibody (Ab) responses toward conserved regions of the viral Envelope (Env). However, the generation of neutralizing Abs (NAbs) targeting these regions through vaccination has proven to be difficult. One conserved region of particular interest is the membrane proximal external region (MPER) of Env located within the gp41 ectodomain. In order to direct the immune response to this region, the MPER and gp41 ectodomain were expressed separately as N-terminal fusions to the E2 protein of Geobacillus stearothermophilus. The E2 protein acts as a scaffold by self-assembling into 60-mer particles, displaying up to 60 copies of the fused target on the surface. Rabbits were immunized with E2 particles displaying MPER and/or the gp41 ectodomain in conjunction with DNA encoding full-length gp160. Only vaccines including E2 particles displaying MPER elicited MPER-specific Ab responses. NAbs were elicited after two immunizations that largely targeted the V3 loop. To overcome V3 immunodominance in the DNA component, E2 particles displaying MPER were used in conjunction with gp160 DNA lacking hypervariable regions V2, V3, or combined V1V2V3. All rabbits had HIV binding Ab responses and NAbs following the second vaccination. Using HIV-2/HIV-1 MPER chimeric viruses as targets, NAbs were detected in 12/16 rabbits after three immunizations. Low levels of NAbs specific for Tier 1 and 2 viruses were observed in all groups. This study provides evidence that co-immunizing E2 particles displaying MPER and gp160 DNA can focus Ab responses toward conserved regions of Env. PMID:25514675

  19. Ion Acoustic Waves in Ultracold Neutral Plasmas

    SciTech Connect

    Castro, J.; McQuillen, P.; Killian, T. C.

    2010-08-06

    We photoionize laser-cooled atoms with a laser beam possessing spatially periodic intensity modulations to create ultracold neutral plasmas with controlled density perturbations. Laser-induced fluorescence imaging reveals that the density perturbations oscillate in space and time, and the dispersion relation of the oscillations matches that of ion acoustic waves, which are long-wavelength, electrostatic, density waves.

  20. Tautomerism in neutral histidine.

    PubMed

    Bermúdez, Celina; Mata, Santiago; Cabezas, Carlos; Alonso, José L

    2014-10-01

    Histidine is an important natural amino acid, involved in many relevant biological processes, which, because of its physical properties, proved difficult to characterize experimentally in its neutral form. In this work, neutral histidine has been generated in the gas phase by laser ablation of solid samples and its N(ε)H tautomeric form unraveled through its rotational spectrum. The quadrupole hyperfine structure, arising from the existing three (14)N nuclei, constituted a site-specifically probe for revealing the tautomeric form as well as the side chain configuration of this proteogenic amino acid.

  1. The IKK-neutralizing compound Bay11 kills supereffector CD8 T cells by altering caspase-dependent activation-induced cell death.

    PubMed

    Lee, Seung-Joo; Long, Meixiao; Adler, Adam J; Mittler, Robert S; Vella, Anthony T

    2009-01-01

    Antigen with dual costimulation through CD137 and CD134 induces powerful CD8 T cell responses. These effector T cells are endowed with an intrinsic survival program resulting in their accumulation in vivo, but the signaling components required for survival are unknown. We tested a cadre of pathway inhibitors and found one preclinical compound, Bay11-7082 (Bay11), which prevented survival. Even the gammac cytokine family members IL-2, -4, -7, and -15 could not block death, nor could pretreatment with IL-7. We found that dual costimulation caused loading of phosphorylated IkappaBalpha (p-IkappaBalpha) and high basal levels of NF-kappaB activity in the effector CD8 T cells. Bay11 trumped both events by reducing the presence of p-IkappaBalpha and ensuing NF-kappaB activity. Not all pathways were impacted to this degree, however, as mitogen-mediated ERK phosphorylation was evident during NF-kappaB inhibition. Nonetheless, Bay11 blocked TCR-stimulated cytokine synthesis by rapidly accentuating activation-induced cell death through elicitation of a caspase-independent pathway. Thus, in effector CD8 T cells, Bay11 forces a dominant caspase-independent death signal that cannot be overcome by an intrinsic survival program nor by survival-inducing cytokines. Therefore, Bay11 may be a useful tool to deliberately kill death-resistant effector T cells for therapeutic benefit.

  2. CO2-Neutral Fuels

    NASA Astrophysics Data System (ADS)

    Goede, Adelbert; van de Sanden, Richard

    2016-06-01

    Mimicking the biogeochemical cycle of System Earth, synthetic hydrocarbon fuels are produced from recycled CO2 and H2O powered by renewable energy. Recapturing CO2 after use closes the carbon cycle, rendering the fuel cycle CO2 neutral. Non-equilibrium molecular CO2 vibrations are key to high energy efficiency.

  3. Bleach Neutralizes Mold Allergens

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Researchers at National Jewish Medical and Research Center have demonstrated that dilute bleach not only kills common household mold, but may also neutralize the mold allergens that cause most mold-related health complaints. The study, published in the Journal of Allergy and Clinical Immunology, is the first to test the effect on allergic…

  4. Nanogel-based pneumococcal surface protein A nasal vaccine induces microRNA-associated Th17 cell responses with neutralizing antibodies against Streptococcus pneumoniae in macaques.

    PubMed

    Fukuyama, Y; Yuki, Y; Katakai, Y; Harada, N; Takahashi, H; Takeda, S; Mejima, M; Joo, S; Kurokawa, S; Sawada, S; Shibata, H; Park, E J; Fujihashi, K; Briles, D E; Yasutomi, Y; Tsukada, H; Akiyoshi, K; Kiyono, H

    2015-09-01

    We previously established a nanosized nasal vaccine delivery system by using a cationic cholesteryl group-bearing pullulan nanogel (cCHP nanogel), which is a universal protein-based antigen-delivery vehicle for adjuvant-free nasal vaccination. In the present study, we examined the central nervous system safety and efficacy of nasal vaccination with our developed cCHP nanogel containing pneumococcal surface protein A (PspA-nanogel) against pneumococcal infection in nonhuman primates. When [(18)F]-labeled PspA-nanogel was nasally administered to a rhesus macaque (Macaca mulatta), longer-term retention of PspA was noted in the nasal cavity when compared with administration of PspA alone. Of importance, no deposition of [(18)F]-PspA was seen in the olfactory bulbs or brain. Nasal PspA-nanogel vaccination effectively induced PspA-specific serum IgG with protective activity and mucosal secretory IgA (SIgA) Ab responses in cynomolgus macaques (Macaca fascicularis). Nasal PspA-nanogel-induced immune responses were mediated through T-helper (Th) 2 and Th17 cytokine responses concomitantly with marked increases in the levels of miR-181a and miR-326 in the serum and respiratory tract tissues, respectively, of the macaques. These results demonstrate that nasal PspA-nanogel vaccination is a safe and effective strategy for the development of a nasal vaccine for the prevention of pneumonia in humans. PMID:25669148

  5. Nanogel-based pneumococcal surface protein A nasal vaccine induces microRNA-associated Th17 cell responses with neutralizing antibodies against Streptococcus pneumoniae in macaques

    PubMed Central

    Fukuyama, Y; Yuki, Y; Katakai, Y; Harada, N; Takahashi, H; Takeda, S; Mejima, M; Joo, S; Kurokawa, S; Sawada, S; Shibata, H; Park, E J; Fujihashi, K; Briles, D E; Yasutomi, Y; Tsukada, H; Akiyoshi, K; Kiyono, H

    2015-01-01

    We previously established a nanosized nasal vaccine delivery system by using a cationic cholesteryl group-bearing pullulan nanogel (cCHP nanogel), which is a universal protein-based antigen-delivery vehicle for adjuvant-free nasal vaccination. In the present study, we examined the central nervous system safety and efficacy of nasal vaccination with our developed cCHP nanogel containing pneumococcal surface protein A (PspA-nanogel) against pneumococcal infection in nonhuman primates. When [18F]-labeled PspA-nanogel was nasally administered to a rhesus macaque (Macaca mulatta), longer-term retention of PspA was noted in the nasal cavity when compared with administration of PspA alone. Of importance, no deposition of [18F]-PspA was seen in the olfactory bulbs or brain. Nasal PspA-nanogel vaccination effectively induced PspA-specific serum IgG with protective activity and mucosal secretory IgA (SIgA) Ab responses in cynomolgus macaques (Macaca fascicularis). Nasal PspA-nanogel-induced immune responses were mediated through T-helper (Th) 2 and Th17 cytokine responses concomitantly with marked increases in the levels of miR-181a and miR-326 in the serum and respiratory tract tissues, respectively, of the macaques. These results demonstrate that nasal PspA-nanogel vaccination is a safe and effective strategy for the development of a nasal vaccine for the prevention of pneumonia in humans. PMID:25669148

  6. Identification and characterization of a cDNA encoding a crustin-like, putative antibacterial protein from the American lobster Homarus americanus.

    PubMed

    Christie, Andrew E; Rus, Szymon; Goiney, Christopher C; Smith, Christine M; Towle, David W; Dickinson, Patsy S

    2007-07-01

    Pathogenic challenges in decapod crustaceans are combated by innate immune responses, including the production and secretion of soluble antibacterial proteins into the hemolymph. Among the antibacterials that have been identified in decapod species are the crustins, a group of four-disulfide core/whey-acidic-protein (WAP) domain-containing proteins, which target marine/salt tolerant Gram-positive bacteria. To begin to assess the possible role of crustins in combating bacterial invasion in the American lobster Homarus americanus, we identified and sequenced a 744 base pair cDNA that encodes a novel 96 amino acid crustin-like protein. Comparison of H. americanus crustin (Hoa-crustin) with crustins from other decapod species showed that it is most similar to an isoform predicted from the European lobster Homarus gammarus ( approximately 86% identity). With our identification of the Hoa-crustin cDNA, we are positioned to begin molecular and physiological investigations of the regulation and function of this putative antibacterial protein in H. americanus. PMID:17418897

  7. Neutral reactors on shunt compensated EHV lines

    SciTech Connect

    Atmuri, S.R.; Thallam, R.S.; Gerlach, D.W.; Lundquist, T.G.; Selin, D.A.

    1994-12-31

    This paper examines the applications of a neutral reactor in limiting resonance overvoltages induced on deenergized conductors due to parallel energized circuits and stuck breaker conditions. These applications are demonstrated through the planned 243 mile long Mead-Phoenix 500 kV line running on the same right of way as the existing Mead-Liberty 345 kV line. Reducing the secondary arc current during single pole reclosing is also examined. In addition to its applications, a procedure for sizing, rating and protection of the neutral reactor is explained.

  8. Measurement of {nu}{sub {mu}}and {nu}{sub {mu}}induced neutral current single {pi}{sup 0} production cross sections on mineral oil at E{sub {nu}{approx}O} (1 GeV)

    SciTech Connect

    Aguilar-Arevalo, A. A.; Anderson, C. E.; Curioni, A.; Fleming, B. T.; Linden, S. K.; Soderberg, M.; Spitz, J.; Bazarko, A. O.; Laird, E. M.; Meyers, P. D.; Patterson, R. B.; Shoemaker, F. C.; Tanaka, H. A.; Brice, S. J.; Brown, B. C.; Finley, D. A.; Ford, R.; Garcia, F. G.; Kasper, P.; Kobilarcik, T.

    2010-01-01

    MiniBooNE reports the first absolute cross sections for neutral current single {pi}{sup 0} production on CH{sub 2} induced by neutrino and antineutrino interactions measured from the largest sets of NC {pi}{sup 0} events collected to date. The principal result consists of differential cross sections measured as functions of {pi}{sup 0} momentum and {pi}{sup 0} angle averaged over the neutrino flux at MiniBooNE. We find total cross sections of (4.76{+-}0.05{sub stat{+-}}0.76{sub sys})x10{sup -40} cm{sup 2}/nucleon at a mean energy of }=808 MeV and (1.48{+-}0.05{sub stat{+-}}0.23{sub sys})x10{sup -40} cm{sup 2}/nucleon at a mean energy of }=664 MeV for {nu}{sub {mu}}and {nu}{sub {mu}}induced production, respectively. In addition, we have included measurements of the neutrino and antineutrino total cross sections for incoherent exclusive NC 1{pi}{sup 0} production corrected for the effects of final state interactions to compare to prior results.

  9. Elimination of human T cell leukemia virus type-1-infected cells by neutralizing and antibody-dependent cellular cytotoxicity-inducing antibodies against human t cell leukemia virus type-1 envelope gp46.

    PubMed

    Tanaka, Yuetsu; Takahashi, Yoshiaki; Tanaka, Reiko; Kodama, Akira; Fujii, Hideki; Hasegawa, Atsuhiko; Kannagi, Mari; Ansari, Aftab A; Saito, Mineki

    2014-06-01

    Human T cell leukemia virus type-1 (HTLV-1) is prevalent worldwide with foci of high prevalence. However, to date no effective vaccine or drug against HTLV-1 infection has been developed. In efforts to define the role of antibodies in the control of HTLV-1 infection, we capitalized on the use of our previously defined anti-gp46 neutralizing monoclonal antibody (mAb) (clone LAT-27) and high titers of human anti-HTLV-1 IgG purified from HAM/TSP patients (HAM-IgG). LAT-27 and HAM-IgG completely blocked syncytium formation and T cell immortalization mediated by HTLV-1 in vitro. The addition of these antibodies to cultures of CD8(+) T cell-depleted peripheral blood mononuclear cells (PBMCs) from HAM/TSP patients at the initiation of culture not only decreased the numbers of Tax-expressing cells and the production of HTLV-1 p24 but also inhibited the spontaneous immortalization of T cells. Coculture of in vitro-HTLV-1-immortalized T cell lines with autologous PBMCs in the presence of LAT-27 or HAM-IgG, but not an F(ab')2 fragment of LAT-27 or nonneutralizing anti-gp46 mAbs, resulted in depletion of HTLV-1-infected cells. A 24-h (51)Cr release assay showed the presence of significant antibody-dependent cellular cytotoxicity (ADCC) activity in LAT-27 and HAM-IgG, but not F(ab')2 of LAT-27, resulting in the depletion of HTLV-1-infected T cells by autologous PBMCs. The depletion of natural killer (NK) cells from the effector PBMCs reduced this ADCC activity. Altogether, the present data demonstrate that the neutralizing and ADCC-inducing activities of anti-HTLV-1 antibodies are capable of reducing infection and eliminating HTLV-1-infected cells in the presence of autologous PBMCs. PMID:24524420

  10. Whole-Chain Tick Saliva Proteins Presented on Hepatitis B Virus Capsid-Like Particles Induce High-Titered Antibodies with Neutralizing Potential.

    PubMed

    Kolb, Philipp; Wallich, Reinhard; Nassal, Michael

    2015-01-01

    Ticks are vectors for various, including pathogenic, microbes. Tick saliva contains multiple anti-host defense factors that enable ticks their bloodmeals yet also facilitate microbe transmission. Lyme disease-causing borreliae profit specifically from the broadly conserved tick histamine release factor (tHRF), and from cysteine-rich glycoproteins represented by Salp15 from Ixodes scapularis and Iric-1 from Ixodes ricinus ticks which they recruit to their outer surface protein C (OspC). Hence these tick proteins are attractive targets for anti-tick vaccines that simultaneously impair borrelia transmission. Main obstacles are the tick proteins´ immunosuppressive activities, and for Salp15 orthologs, the lack of efficient recombinant expression systems. Here, we exploited the immune-enhancing properties of hepatitis B virus core protein (HBc) derived capsid-like particles (CLPs) to generate, in E. coli, nanoparticulate vaccines presenting tHRF and, as surrogates for the barely soluble wild-type proteins, cysteine-free Salp15 and Iric-1 variants. The latter CLPs were exclusively accessible in the less sterically constrained SplitCore system. Mice immunized with tHRF CLPs mounted a strong anti-tHRF antibody response. CLPs presenting cysteine-free Salp15 and Iric-1 induced antibodies to wild-type, including glycosylated, Salp15 and Iric-1. The broadly distributed epitopes included the OspC interaction sites. In vitro, the anti-Salp15 antibodies interfered with OspC binding and enhanced human complement-mediated killing of Salp15 decorated borreliae. A mixture of all three CLPs induced high titered antibodies against all three targets, suggesting the feasibility of combination vaccines. These data warrant in vivo validation of the new candidate vaccines´ protective potential against tick infestation and Borrelia transmission.

  11. Whole-Chain Tick Saliva Proteins Presented on Hepatitis B Virus Capsid-Like Particles Induce High-Titered Antibodies with Neutralizing Potential

    PubMed Central

    Kolb, Philipp; Wallich, Reinhard; Nassal, Michael

    2015-01-01

    Ticks are vectors for various, including pathogenic, microbes. Tick saliva contains multiple anti-host defense factors that enable ticks their bloodmeals yet also facilitate microbe transmission. Lyme disease-causing borreliae profit specifically from the broadly conserved tick histamine release factor (tHRF), and from cysteine-rich glycoproteins represented by Salp15 from Ixodes scapularis and Iric-1 from Ixodes ricinus ticks which they recruit to their outer surface protein C (OspC). Hence these tick proteins are attractive targets for anti-tick vaccines that simultaneously impair borrelia transmission. Main obstacles are the tick proteins´ immunosuppressive activities, and for Salp15 orthologs, the lack of efficient recombinant expression systems. Here, we exploited the immune-enhancing properties of hepatitis B virus core protein (HBc) derived capsid-like particles (CLPs) to generate, in E. coli, nanoparticulate vaccines presenting tHRF and, as surrogates for the barely soluble wild-type proteins, cysteine-free Salp15 and Iric-1 variants. The latter CLPs were exclusively accessible in the less sterically constrained SplitCore system. Mice immunized with tHRF CLPs mounted a strong anti-tHRF antibody response. CLPs presenting cysteine-free Salp15 and Iric-1 induced antibodies to wild-type, including glycosylated, Salp15 and Iric-1. The broadly distributed epitopes included the OspC interaction sites. In vitro, the anti-Salp15 antibodies interfered with OspC binding and enhanced human complement-mediated killing of Salp15 decorated borreliae. A mixture of all three CLPs induced high titered antibodies against all three targets, suggesting the feasibility of combination vaccines. These data warrant in vivo validation of the new candidate vaccines´ protective potential against tick infestation and Borrelia transmission. PMID:26352137

  12. Broadly neutralizing antibodies against influenza viruses

    PubMed Central

    Laursen, Nick S.; Wilson, Ian A.

    2014-01-01

    Despite available antivirals and vaccines, influenza infections continue to be a major cause of mortality worldwide. Vaccination generally induces an effective, but strain-specific antibody response. As the virus continually evolves, new vaccines have to be administered almost annually when a novel strain becomes dominant. Furthermore, the sporadic emerging resistance to neuraminidase inhibitors among circulating strains suggests an urgent need for new therapeutic agents. Recently, several cross-reactive antibodies have been described, which neutralize an unprecedented spectrum of influenza viruses. These broadly neutralizing antibodies generally target conserved functional regions on the major influenza surface glycoprotein hemagglutinin (HA). The characterization of their neutralization breadth and epitopes on HA could stimulate the development of new antibody-based antivirals and broader influenza vaccines. PMID:23583287

  13. Between detection and neutralization.

    SciTech Connect

    Snell, Mark Kamerer; Green, Mary Wilson; Adams, Douglas Glenn; Pritchard, Daniel Allison

    2005-08-01

    Security system analytical performance analysis is generally based on the probability of system effectiveness. The probability of effectiveness is a function of the probabilities of interruption and neutralization. Interruption occurs if the response forces are notified in sufficient time to engage the adversary. Neutralization occurs if the adversary attack is defeated after the security forces have actively engaged the adversary. Both depend upon communications of data. This paper explores details of embedded communications functions that are often assumed to be inconsequential. It is the intent of the authors to bring focus to an issue in security system modeling that, if not well understood, has the potential to be a deciding factor in the overall system failure or effectiveness.

  14. Neutral particle beam intensity controller

    DOEpatents

    Dagenhart, William K.

    1986-01-01

    A neutral beam intensity controller is provided for a neutral beam generator in which a neutral beam is established by accelerating ions from an ion source into a gas neutralizer. An amplitude modulated, rotating magnetic field is applied to the accelerated ion beam in the gas neutralizer to defocus the resultant neutral beam in a controlled manner to achieve intensity control of the neutral beam along the beam axis at constant beam energy. The rotating magnetic field alters the orbits of ions in the gas neutralizer before they are neutralized, thereby controlling the fraction of neutral particles transmitted out of the neutralizer along the central beam axis to a fusion device or the like. The altered path or defocused neutral particles are sprayed onto an actively cooled beam dump disposed perpendicular to the neutral beam axis and having a central open for passage of the focused beam at the central axis of the beamline. Virtually zero therough 100% intensity control is achieved by varying the magnetic field strength without altering the ion source beam intensity or its species yield.

  15. Antihypertensive neutral lipid

    DOEpatents

    Snyder, F.L.; Blank, M.L.

    1984-10-26

    The invention relates to the discovery of a class of neutral acetylated either-linked glycerolipids having the capacity to lower blood presure in warm-blooded animals. This physiological effect is structure sensitive requiring a long chain alkyl group at the sn-1 position and a short carbon chain acyl group (acetyl or propionyl) at the sn-2 position, and a hydroxyl group at the sn-3 position.

  16. Antihypertensive neutral lipid

    DOEpatents

    Snyder, Fred L.; Blank, Merle L.

    1986-01-01

    The invention relates to the discovery of a class of neutral acetylated ether-linked glycerolipids having the capacity to lower blood pressure in warm-blooded animals. This physiological effect is structure sensitive requiring a long chain alkyl group at the sn-1 position and a short carbon chain acyl group (acetyl or propionyl) at the sn-2 position, and a hydroxyl group at the sn-3 position.

  17. Exercise Equipment: Neutral Buoyancy

    NASA Technical Reports Server (NTRS)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  18. Neutral Buoyancy Simulator Test

    NASA Technical Reports Server (NTRS)

    1995-01-01

    A diver tests a secondary camera and maneuvering platform in Marshall's Neutral Buoyancy Simulator (NBS).The secondary camera will be beneficial for recording repairs and other extra vehicular activities (EVA) the astronuats will perform while making repairs on the Hubble Space Telescope (HST). The maneuvering platform was developed to give the astronauts something to stand on while performing maintenance tasks. These platforms were developed to be mobile so that the astronauts could move them to accommadate different sites.

  19. Neutralization of adenoviruses: kinetics, stoichiometry, and mechanisms.

    PubMed Central

    Wohlfart, C

    1988-01-01

    Kinetic curves for neutralization of adenovirus type 2 with anti-hexon serum revealed no lag periods even when the serum was highly diluted or when the temperature was lowered to 4 degrees C, thus indicating a single-hit mechanism. Multiplicity curves determined with anti-hexon serum displayed a linear correlation between the degree of neutralization and dilution of antiserum. Neutralization values experimentally obtained under steady-state conditions fully fitted a single-hit model based on Poisson calculations. Quantitation of the amount of 125I-labeled type-specific anti-hexon antibodies needed for full neutralization of adenovirus showed that 1.4 antibodies were attached per virion under such conditions. Virions already attached to HeLa cells at 4 degrees C were, to a large extent, neutralizable by anti-hexon serum, whereas anti-fiber and anti-penton base antisera were negative. It is suggested that adenovirus may be neutralized by two pathways: aggregation of the virions (extracellular neutralization) as performed by anti-fiber antibodies and blocking of virion entrance from the acidic endosomes into the cytoplasm (intracellular neutralization). The latter effect could be obtained by (i) covering of the penton bases, as performed by anti-penton base antibodies, thereby preventing interaction between the penton bases and the endosomal membrane, which results in trapping of virions within endosomes, and (ii) inhibition of the low-pH-induced conformational change of the viral capsid, which seems to occur in the endosomes and is necessary for proper exposure of the penton bases, as performed by anti-hexon antibodies. Images PMID:3373570

  20. Neutral particle beam intensity controller

    DOEpatents

    Dagenhart, W.K.

    1984-05-29

    The neutral beam intensity controller is based on selected magnetic defocusing of the ion beam prior to neutralization. The defocused portion of the beam is dumped onto a beam dump disposed perpendicular to the beam axis. Selective defocusing is accomplished by means of a magnetic field generator disposed about the neutralizer so that the field is transverse to the beam axis. The magnetic field intensity is varied to provide the selected partial beam defocusing of the ions prior to neutralization. The desired focused neutral beam portion passes along the beam path through a defining aperture in the beam dump, thereby controlling the desired fraction of neutral particles transmitted to a utilization device without altering the kinetic energy level of the desired neutral particle fraction. By proper selection of the magnetic field intensity, virtually zero through 100% intensity control of the neutral beam is achieved.

  1. rRNA operons and genome size of 'Candidatus Liberibacter americanus', a bacterium associated with citrus huanglongbing in Brazil.

    PubMed

    Wulff, N A; Eveillard, S; Foissac, X; Ayres, A J; Bové, J-M

    2009-08-01

    Huanglongbing is one of the most severe diseases of citrus worldwide and is associated with 'Candidatus (Ca.) Liberibacter africanus' in Africa, 'Ca. Liberibacter asiaticus' in Asia and the Americas (Brazil, USA and Cuba) and 'Ca. Liberibacter americanus' (Lam) in Brazil. In the absence of axenic cultures, genetic information on liberibacters is scarce. The sequences of the entire 23S rRNA and 5S rRNA genes from Lam have now been obtained, using a consensus primer designed on known tRNAMet sequences of rhizobia. The size of the Lam genome was determined by PFGE, using Lam-infected periwinkle plants for bacterial enrichment, and was found to be close to 1.31 Mbp. In order to determine the number of ribosomal operons on the Lam genome, probes designed to detect the 16S rRNA gene and the 3' end of the 23S rRNA gene were developed and used for Southern hybridization with I-CeuI-treated genomic DNA. Our results suggest that there are three ribosomal operons in a circular genome. Lam is the first liberibacter species for which such data are available.

  2. Cadmium inhibition of L-alanine transport into renal brush border membrane vesicles isolated from the winter flounder (Pseudopleuronectes americanus)

    SciTech Connect

    Bevan, C.; Kinne-Saffran, E.; Foulkes, E.C.; Kinne, R.K. )

    1989-12-01

    Using isolated brush border membrane vesicles from the kidney of the winter flounder (Pseudopleuronectes americanus), we have studied the effect of cadmium on L-alanine transport. Pretreatment of vesicles with 0.1 mM Cd{sup 2+} resulted in inhibition of L-alanine uptake in the presence of a NaCl (but not KCl) gradient. Inhibition was due to a specific interaction with the sodium-alanine cotransport system and not a change in the driving forces for alanine transport, since Cd{sup 2+} did not affect sodium-dependent D-glucose uptake. The effect of Cd{sup 2+} on Na{sup +}-alanine cotransport showed mixed-type inhibition which is only partially reversible by EDTA. Cd{sup 2+} uptake itself was shown to be time and temperature dependent, resulting in binding to both sides of the membrane. No direct correlation was possible between inhibition of L-alanine transport and the amount of Cd{sup 2+} taken up by the membranes. Nevertheless, the striking time dependence of the effect of Cd{sup 2+} on sodium-dependent L-alanine uptake and the inability of EDTA to reverse the inhibitory action of Cd{sup 2+} suggest that Cd{sup 2+} inhibits Na+-alanine cotransport at the cytoplasmic side of the membrane.

  3. Forces generated during stretch in the heart of the lobster Homarus americanus are anisotropic and are altered by neuromodulators.

    PubMed

    Dickinson, E S; Johnson, A S; Ellers, O; Dickinson, P S

    2016-04-15

    Mechanical and neurophysiological anisotropies mediate three-dimensional responses of the heart of ITALIC! Homarus americanus Although hearts ITALIC! in vivoare loaded multi-axially by pressure, studies of invertebrate cardiac function typically use uniaxial tests. To generate whole-heart length-tension curves, stretch pyramids at constant lengthening and shortening rates were imposed uniaxially and biaxially along longitudinal and transverse axes of the beating whole heart. To determine whether neuropeptides that are known to modulate cardiac activity in ITALIC! H. americanusaffect the active or passive components of these length-tension curves, we also performed these tests in the presence of SGRNFLRFamide (SGRN) and GYSNRNYLRFamide (GYS). In uniaxial and biaxial tests, both passive and active forces increased with stretch along both measurement axes. The increase in passive forces was anisotropic, with greater increases along the longitudinal axis. Passive forces showed hysteresis and active forces were higher during lengthening than shortening phases of the stretch pyramid. Active forces at a given length were increased by both neuropeptides. To exert these effects, neuropeptides might have acted indirectly on the muscle via their effects on the cardiac ganglion, directly on the neuromuscular junction, or directly on the muscles. Because increases in response to stretch were also seen in stimulated motor nerve-muscle preparations, at least some of the effects of the peptides are likely peripheral. Taken together, these findings suggest that flexibility in rhythmic cardiac contractions results from the amplified effects of neuropeptides interacting with the length-tension characteristics of the heart.

  4. A New PCR-Based Method Shows That Blue Crabs (Callinectes sapidus (Rathbun)) Consume Winter Flounder (Pseudopleuronectes americanus (Walbaum))

    PubMed Central

    Collier, Jackie L.; Fitzgerald, Sean P.; Hice, Lyndie A.; Frisk, Michael G.; McElroy, Anne E.

    2014-01-01

    Winter flounder (Pseudopleuronectes americanus) once supported robust commercial and recreational fisheries in the New York (USA) region, but since the 1990s populations have been in decline. Available data show that settlement of young-of-the-year winter flounder has not declined as sharply as adult abundance, suggesting that juveniles are experiencing higher mortality following settlement. The recent increase of blue crab (Callinectes sapidus) abundance in the New York region raises the possibility that new sources of predation may be contributing to juvenile winter flounder mortality. To investigate this possibility we developed and validated a method to specifically detect winter flounder mitochondrial control region DNA sequences in the gut contents of blue crabs. A survey of 55 crabs collected from Shinnecock Bay (along the south shore of Long Island, New York) in July, August, and September of 2011 showed that 12 of 42 blue crabs (28.6%) from which PCR-amplifiable DNA was recovered had consumed winter flounder in the wild, empirically supporting the trophic link between these species that has been widely speculated to exist. This technique overcomes difficulties with visual identification of the often unrecognizable gut contents of decapod crustaceans, and modifications of this approach offer valuable tools to more broadly address their feeding habits on a wide variety of species. PMID:24454797

  5. Aerococcus viridans expression of Cpn60 is associated with virulence during infection of the American lobster, Homarus americanus Milne Edwards.

    PubMed

    Clark, K F; Greenwood, S J

    2011-11-01

    The Gram-positive bacterium Aerococcus viridans var. homari is a well-documented causative agent of the lethal systemic disease gaffkemia in both the American lobster, Homarus americanus, and the European lobster, Homarus gammarus. Previous phenotypic characterization has been unsuccessful at differentiating avirulent from virulent strains without performing lethal animal infection trials. Recent genetic characterization of A. viridans strains through 16S rRNA sequencing and random amplification of polymorphic DNA fingerprinting has revealed the presence of two subtypes. However, subtype 1 contains both virulent and avirulent strains which are genetically identical. The purpose of this study was to determine the proteomic mediators of virulence in A. viridans. Quantitative proteomic mapping of these two strains has revealed 29 differentially expressed protein spots, seven of which are only expressed in the virulent strain and could act as virulence factors. One protein, chaperonin 60 (Cpn60), is uniquely expressed in the virulent strain and has been shown to act as a virulence factor in many other bacteria. The proteomic mapping strategy employed in this study is the first to show phenotypic differences between virulent and avirulent strains. Cpn60 expression represents a potentially useful tool for identifying the virulent strains of A. viridans in epidemiological studies. PMID:21988355

  6. 1-/sup 14/C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus

    SciTech Connect

    Little, P.J.; James, M.O.; Foureman, G.L.; Weatherby, R.P.; Bend, J.R.

    1986-05-01

    1-/sup 14/C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for /sup 14/C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).

  7. Copper-metallothioneins in the American lobster, Homarus americanus: potential role as Cu(I) donors to apohemocyanin

    SciTech Connect

    Brouwer, M.; Whaling, P.; Engel, D.W.

    1986-03-01

    The physiological function of copper(I)-metallothionein is not well understood. The respiratory function of hemocyanin, a copper(I)-containing respiratory protein found in the hemolymph of many invertebrates, has been known a long time. However, the mechanism by which Cu(I) is inserted into the oxygen-binding site of apohemocyanin is completely unknown. This investigation tests that hypothesis that copper(I)-metallothionein may act as a Cu(I) donor to apohemocyanin. To this end, copper-binding proteins and hemocyanin were purified from the digestive gland and hemolymph of the American lobster, Homarus americanus. In the presence of ..beta..-mercaptoethanol, the copper-binding proteins can be resolved into three components of DEAE-cellulose. The first two have been characterized as metallothioneins. The cysteine content of the third component is half of that of components I and II. The purified proteins are not capable of transferring Cu(I) to the active sites of completely copper-free apohemocyanin. They are capable, however, of transferring Cu(I) to active sites of hemocyanin containing reduced amounts of Cu(I), suggesting that the conformational state of hemocyanin is the determining factor in the Cu(I) transfer mechanism.

  8. Magnetic resonance imaging diagnosis of intervertebral disc disease and myelomalacia in an American black bear (Ursus americanus).

    PubMed

    Knafo, S Emmanuelle; Divers, Stephen J; Rech, Raquel; Platt, Simon R

    2012-06-01

    A 23-yr-old black bear (Ursus americanus) was examined because of paralysis of unknown duration. The precise onset of clinical signs was unknown as a result of seasonal torpor. The bear was immobilized and transported to a university veterinary teaching hospital for further evaluation and treatment. Radiography revealed increased mineral opacity and ventral bridging across vertebral segments T8-11. Magnetic resonance imaging demonstrated dorsal and ventral compression of the spinal cord at T8-9. Given the bear's advanced age, the unknown duration of spinal cord compression, unknown presence of deep pain perception, and thus an unknown prognosis for surgical success, euthanasia was elected. Postmortem examination revealed severe spondylosis deformans from T7 to L3 and dorsal extradural extruded disc material in the area of T8-9. Histopathology demonstrated the dorsal horns of the spinal cord at T9 were replaced by foamy macrophages extending into the dorsal and lateral funiculi of the white matter compatible with focal, severe, chronic myelomalacia. This is the first report of intervertebral disc disease and myelomalacia diagnosed using MRI in a large carnivore. PMID:22779249

  9. The effects of hibernation and captivity on glucose metabolism and thyroid hormones in American black bear (Ursus americanus).

    PubMed

    McCain, Stephanie; Ramsay, Ed; Kirk, Claudia

    2013-06-01

    American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined insulin and glucose tolerance tests and thyroid hormone profiles were performed on all bears during each stage. All three groups of bears had evidence of insulin resistance during the winter, as compared to the summer or fall, based on glucose tolerance curves. Analysis of thyroid hormone concentration varied and distinct patterns or similarities were not apparent. While obesity in captive American black bears is multifactorial, the finding that, regardless of their ability to hibernate, captive bears retain similar physiology to their wild counterparts indicates that captive bears' complex physiologic changes need to be addressed in their management. PMID:23805551

  10. Identification and phylogenetic analysis of Dirofilaria ursi (Nematoda: Filarioidea) from Wisconsin black bears (Ursus americanus) and its Wolbachia endosymbiont.

    PubMed

    Michalski, Michelle L; Bain, Odile; Fischer, Kerstin; Fischer, Peter U; Kumar, Sanjay; Foster, Jeremy M

    2010-04-01

    Dirofilaria ursi is a filarial nematode of American black bears (Ursus americanus Pallas, 1780) that is vectored by black flies (Simuliidae) in many parts of the United States. In northwestern Wisconsin, the prevalence of microfilaremic bears during the fall hunting season was 21% (n = 47). Unsheathed blood microfilariae from Wisconsin bears possess characters consistent with the original description of D. ursi, as do adult worms observed histologically and grossly. Immunohistochemistry was used to identify the Wolbachia endosymbiont in the hypodermis and lateral cords of an adult female D. ursi. Amplification of wsp, gatB, coxA, fbpA, and ftsZ bacterial sequences from parasite DNA confirmed the presence of Wolbachia, and molecular phylogenetic analysis of the Wolbachia ftsZ gene groups the endosymbiont with Wolbachia from D. immitis and D. repens. Phylogenetic analysis of D. ursi 5s rDNA sequence confirms the morphological observations grouping this parasite as a member of Dirofilaria, and within the Dirofilaria - Onchocerca clade of filarial nematodes. This is the first report of Wolbachia characterization and molecular phylogeny information for D. ursi. PMID:19916630

  11. First evidence for slave rebellion: enslaved ant workers systematically kill the brood of their social parasite protomognathus americanus.

    PubMed

    Achenbach, Alexandra; Foitzik, Susanne

    2009-04-01

    During the process of coevolution, social parasites have evolved sophisticated strategies to exploit the brood care behavior of their social hosts. Slave-making ant queens invade host colonies and kill or eject all adult host ants. Host workers, which eclose from the remaining brood, are tricked into caring for the parasite brood. Due to their high prevalence and frequent raids, following which stolen host broods are similarly enslaved, slave-making ants exert substantial selection upon their hosts, leading to the evolution of antiparasite adaptations. However, all host defenses shown to date are active before host workers are parasitized, whereas selection was thought to be unable to act on traits of already enslaved hosts. Yet, here we demonstrate the rebellion of enslaved Temnothorax workers, which kill two-thirds of the female pupae of the slave-making ant Protomognathus americanus. Thereby, slaves decrease the long-term parasite impact on surrounding related host colonies. This novel antiparasite strategy of enslaved workers constitutes a new level in the coevolutionary battle after host colony defense has failed. Our discovery is analogous to recent findings in hosts of avian brood parasites where perfect mimicry of parasite eggs leads to the evolution of chick recognition as a second line of defense.

  12. The effects of hibernation and captivity on glucose metabolism and thyroid hormones in American black bear (Ursus americanus).

    PubMed

    McCain, Stephanie; Ramsay, Ed; Kirk, Claudia

    2013-06-01

    American black bears (Ursus americanus) have been shown to become transiently insulin resistant and hypothyroid during winter, but no studies have investigated these changes in long-term captive bears or in bears which remain awake year-round. Wild, captive hibernating, and captive nonhibernating bears were evaluated at times corresponding to three of their major physiologic stages: fall (hyperphagic stage), winter (hibernation stage), and summer (normal activity stage). Combined insulin and glucose tolerance tests and thyroid hormone profiles were performed on all bears during each stage. All three groups of bears had evidence of insulin resistance during the winter, as compared to the summer or fall, based on glucose tolerance curves. Analysis of thyroid hormone concentration varied and distinct patterns or similarities were not apparent. While obesity in captive American black bears is multifactorial, the finding that, regardless of their ability to hibernate, captive bears retain similar physiology to their wild counterparts indicates that captive bears' complex physiologic changes need to be addressed in their management.

  13. Forces generated during stretch in the heart of the lobster Homarus americanus are anisotropic and are altered by neuromodulators.

    PubMed

    Dickinson, E S; Johnson, A S; Ellers, O; Dickinson, P S

    2016-04-15

    Mechanical and neurophysiological anisotropies mediate three-dimensional responses of the heart of ITALIC! Homarus americanus Although hearts ITALIC! in vivoare loaded multi-axially by pressure, studies of invertebrate cardiac function typically use uniaxial tests. To generate whole-heart length-tension curves, stretch pyramids at constant lengthening and shortening rates were imposed uniaxially and biaxially along longitudinal and transverse axes of the beating whole heart. To determine whether neuropeptides that are known to modulate cardiac activity in ITALIC! H. americanusaffect the active or passive components of these length-tension curves, we also performed these tests in the presence of SGRNFLRFamide (SGRN) and GYSNRNYLRFamide (GYS). In uniaxial and biaxial tests, both passive and active forces increased with stretch along both measurement axes. The increase in passive forces was anisotropic, with greater increases along the longitudinal axis. Passive forces showed hysteresis and active forces were higher during lengthening than shortening phases of the stretch pyramid. Active forces at a given length were increased by both neuropeptides. To exert these effects, neuropeptides might have acted indirectly on the muscle via their effects on the cardiac ganglion, directly on the neuromuscular junction, or directly on the muscles. Because increases in response to stretch were also seen in stimulated motor nerve-muscle preparations, at least some of the effects of the peptides are likely peripheral. Taken together, these findings suggest that flexibility in rhythmic cardiac contractions results from the amplified effects of neuropeptides interacting with the length-tension characteristics of the heart. PMID:26896540

  14. Neutralization by Acetyl Salicylic Acid of the Testosterone induced Impaired Maspin Synthesis Stimulated by Estriol in Neutrophils through Nitric Oxide Synthesis

    PubMed Central

    Manna, Emili; Bank, Sarbashri; Maiti, Smarajit; Jana, Pradipta; Sinha, Asru K.

    2015-01-01

    Purpose: Maspin, an anti breast cancer protein in the mammary cell and normal neutrophil has been reported to be synthesised by the stimulation of NO production induced by estriol. The role of testosterone was investigated in the synthesis of maspin in relation to that of estriol. Methods: Fifty normal female between the ages of 25-65 years old participated in the study. Maspin synthesis was demonstrated by in vitro translation of maspin mRNA, followed by the quantification of maspin by enzyme linked immune absorbent assay. NO was determined by methomoglobin method. Results: Incubation of the neutrophils in HBSS both with 30 nM estriol resulted in the synthesis of 1.8 ngm maspin with simultaneous increase of NO synthesis. In contrast incubating neutrophils with 20 nM testosterone in the presence of estriol inhibited maspin synthesis to 0.33 nM with simultaneous inhibition of NO synthesis from 1.89 nM to 0 nM at the same time. Addition of 0.2 μM flutamide, a testosterone receptor blocker to the incubation mixture restored the synthesis of maspin by 60.64 %. Incubation of 25 μM aspirin that stimulated NO synthesis restored the inhibition of maspin synthesis by testosterone by 79.1%. I-NAME, an inhibitor of nitric oxide synthase, abolished both maspin and NO synthesis. Scatchard plot of estriol binding in the presence of testosterone demonstrated that the male sex hormone inhibited the female sex hormone binding to its receptor by “cross talk” between the receptors. It was found that while 1.02 × 103 molecules of estriol bind each neutrophil at equilibrium, in the presence of testosterone (20 nM) in the binding mixture decreases the binding of estriol to 0.5 × 103 with little change in the dissociation constant compared to controls. Conclution: Estriol was found to stimulate maspin synthesis through the stimulation of NO, testosterone inhibited maspin synthesis through the inhibition of NO synthesis. PMID:26759534

  15. Laser ablated zirconium plasma: A source of neutral zirconium

    SciTech Connect

    Yadav, Dheerendra; Thareja, Raj K.

    2010-10-15

    The authors report spectroscopic investigations of laser produced zirconium (Zr) plasma at moderate laser fluence. At low laser fluence the neutral zirconium species are observed to dominate over the higher species of zirconium. Laser induced fluorescence technique is used to study the velocity distribution of ground state neutral zirconium species. Two-dimensional time-resolved density distributions of ground state zirconium is mapped using planner laser induced fluorescence imaging and total ablated mass of neutral zirconium atoms is estimated. Temporal and spatial evolutions of electron density and temperature are discussed by measuring Stark broadened profile and ratio of intensity of emission lines, respectively.

  16. Neutrality between Government and Religion.

    ERIC Educational Resources Information Center

    Mawdsley, Ralph D.

    1996-01-01

    The overall guiding principle of neutrality between government and religion masks a tension that exists between free exercise of religion and establishment of religion. Reviews the development and current status of "Lemon" as a test for neutrality; proposes a new test for neutrality, evenhandedness, that is common to both the Free Exercise and…

  17. Evidence for persistent Bovine viral diarrhea virus infection in a captive mountain goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Dark, Michael J; Bradway, Daniel S; Ridpath, Julia F; Call, Neill; Haruna, Julius; Rurangirwa, Fred R; Evermann, James F

    2008-11-01

    Bovine viral diarrhea (BVD) viruses are pestiviruses that have been isolated from domestic and wild ruminants. There is serologic evidence of pestiviral infection in more than 40 species of free-range and captive mammals. Vertical transmission can produce persistently infected animals that are immunotolerant to the infecting strain of Bovine viral diarrhea virus (BVDV) and shed virus throughout their lives. Seven species (white-tailed deer, mouse deer, eland, domestic cattle, alpaca, sheep, and pigs) have been definitively identified as persistently infected with BVDV. This study provides serological, molecular, immunohistochemical, and histological evidence for BVDV infection in 2 captive mountain goats from a zoological park in Idaho. The study was triggered by isolation of BVDV from tissues and immunohistochemical identification of viral antigen within lesions of a 7-month-old male mountain goat (goat 1). Blood was collected from other mountain goats and white-tailed and mule deer on the premises for BVDV serum neutralization, viral isolation, and reverse transcription polymerase chain reaction. One 3-month-old mountain goat (goat 2) was antibody negative and BVDV positive in serum samples collected 3 months apart. This goat subsequently died, and though still antibody negative, BVDV was isolated from tissues and identified by immunohistochemistry within lesions. Sequencing and phylogenetic analysis identified the isolates as BVDV-2. These findings provide evidence of persistent infection in a mountain goat, underscoring the need for pestivirus control strategies for wild ruminants in zoological collections. PMID:18987224

  18. Evidence for persistent Bovine viral diarrhea virus infection in a captive mountain goat (Oreamnos americanus).

    PubMed

    Nelson, Danielle D; Dark, Michael J; Bradway, Daniel S; Ridpath, Julia F; Call, Neill; Haruna, Julius; Rurangirwa, Fred R; Evermann, James F

    2008-11-01

    Bovine viral diarrhea (BVD) viruses are pestiviruses that have been isolated from domestic and wild ruminants. There is serologic evidence of pestiviral infection in more than 40 species of free-range and captive mammals. Vertical transmission can produce persistently infected animals that are immunotolerant to the infecting strain of Bovine viral diarrhea virus (BVDV) and shed virus throughout their lives. Seven species (white-tailed deer, mouse deer, eland, domestic cattle, alpaca, sheep, and pigs) have been definitively identified as persistently infected with BVDV. This study provides serological, molecular, immunohistochemical, and histological evidence for BVDV infection in 2 captive mountain goats from a zoological park in Idaho. The study was triggered by isolation of BVDV from tissues and immunohistochemical identification of viral antigen within lesions of a 7-month-old male mountain goat (goat 1). Blood was collected from other mountain goats and white-tailed and mule deer on the premises for BVDV serum neutralization, viral isolation, and reverse transcription polymerase chain reaction. One 3-month-old mountain goat (goat 2) was antibody negative and BVDV positive in serum samples collected 3 months apart. This goat subsequently died, and though still antibody negative, BVDV was isolated from tissues and identified by immunohistochemistry within lesions. Sequencing and phylogenetic analysis identified the isolates as BVDV-2. These findings provide evidence of persistent infection in a mountain goat, underscoring the need for pestivirus control strategies for wild ruminants in zoological collections.

  19. Pulsed field sample neutralization

    DOEpatents

    Appelhans, Anthony D.; Dahl, David A.; Delmore, James E.

    1990-01-01

    An apparatus and method for alternating voltage and for varying the rate of extraction during the extraction of secondary particles, resulting in periods when either positive ions, or negative ions and electrons are extracted at varying rates. Using voltage with alternating charge during successive periods to extract particles from materials which accumulate charge opposite that being extracted causes accumulation of surface charge of opposite sign. Charge accumulation can then be adjusted to a ratio which maintains a balance of positive and negative charge emission, thus maintaining the charge neutrality of the sample.

  20. Inhibition of Neutral red photolysis with different antioxidants.

    PubMed

    Rimpapa, Zlatan; Sofić, Emin; Sapcanin, Aida; Toromanović, Jasmin; Tahirović, Ismet

    2007-02-01

    Neutral red is a dye the azine structure which has been used as an acido-base indicator and a dye in histochemistry. In 1960 Goldhaber introduced Neutral red into the medium of resorbing bone cultures to localize the osteoclast in the living cultures. Using time-lapse microcinematography in order to follow the osteoclasts, he reported excellent contrast could be obtained with Neutral red due to the avidity of osteoclasts for this dye. Unfortunately, however, the photodynamic effect resulting from subsequent exposure of these cultures to light precluded this approach, and again in 1963. it was observed that the death of the osteoclasts was probably due to a photodynamic effect related to the dye in the cell, the presence of oxygen and the frequent exposure of light by our time-lapse photography. VIS and UV irradiation induced photolysis of Neutral red, and from Neutral red cation produced with photons a Neutral red radical. This Neutral red radical can be inhibited with action of an antioxidant, such as melatonin, glutathione, ascorbic acid, E vitamin, etc. We developed an assay with Neutral red photolysis which utilizes a VIS and UV irradiation technique for quantification the inhibition of photolysis with action of an antioxidant. In this method Neutral red acts double, as a free radical generator and as a photosensitizer.

  1. Mass spectral characterization of peptide transmitters/hormones in the nervous system and neuroendocrine organs of the American lobster Homarus americanus

    PubMed Central

    Ma, Mingming; Chen, Ruibing; Sousa, Gregory L.; Bors, Eleanor K.; Kwiatkowski, Molly; Goiney, Christopher C.; Goy, Michael F.; Christie, Andrew E.; Li, Lingjun

    2008-01-01

    The American lobster Homarus americanus is a decapod crustacean with both high economic and scientific importance. To facilitate physiological investigations of peptide transmitter/hormone function in this species, we have used matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI-FTMS), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and nanoscale liquid chromatography coupled to electrospray ionization quadrupole time-of-flight tandem mass spectrometry (nanoLC-ESI-Q-TOF-MS/MS) to elucidate the peptidome present in its nervous system and neuroendocrine organs. In total, 84 peptides were identified, including 27 previously known H. americanus peptides (e.g. VYRKPPFNGSIFamide [Val1-SIFamide]), 23 peptides characterized previously from other decapods, but new to the American lobster (e.g. pQTFQYSRGWTNamide [Arg7-corazonin]), and 34 new peptides de novo sequenced/detected for the first time in this study. Of particular note are a novel B-type allatostatin (TNWNKFQGSWamide) and several novel FMRFamide-related peptides, including an unsulfated analog of sulfakinin (GGGEYDDYGHLRFamide), two myosuppressins (QDLDHVFLRFamide and pQDLDHVFLRFamide), and a collection of short neuropeptide F isoforms (e.g. DTSTPALRLRFamide, and FEPSLRLRFamide). Our data also include the first detection of multiple tachykinin-related peptides in a non-brachyuran decapod, as well as the identification of potential individual-specific variants of orcokinin and orcomyotropin-related peptide. Taken collectively, our results not only expand greatly the number of known H. americanus neuropeptides, but also provide a framework for future studies on the physiological roles played by these molecules in this commercially and scientifically important species. PMID:18304551

  2. Expression, purification, and characterization of the Necator americanus aspartic protease-1 (Na-APR-1 (M74)) antigen, a component of the bivalent human hookworm vaccine

    PubMed Central

    Seid, Christopher A; Curti, Elena; Jones, R Mark; Hudspeth, Elissa; Rezende, Wanderson; Pollet, Jeroen; Center, Lori; Versteeg, Leroy; Pritchard, Sonya; Musiychuk, Konstantin; Yusibov, Vidadi; Hotez, Peter J; Bottazzi, Maria Elena

    2015-01-01

    Over 400 million people living in the world's poorest developing nations are infected with hookworms, mostly of the genus Necator americanus. A bivalent human hookworm vaccine composed of the Necator americanus Glutathione S-Transferase-1 (Na-GST-1) and the Necator americanus Aspartic Protease-1 (Na-APR-1 (M74)) is currently under development by the Sabin Vaccine Institute Product Development Partnership (Sabin PDP). Both monovalent vaccines are currently in Phase 1 trials. Both Na-GST-1 and Na-APR-1 antigens are expressed as recombinant proteins. While Na-GST-1 was found to express with high yields in Pichia pastoris, the level of expression of Na-APR-1 in this host was too low to be suitable for a manufacturing process. When the tobacco plant Nicotiana benthamiana was evaluated as an expression system, acceptable levels of solubility, yield, and stability were attained. Observed expression levels of Na-APR-1 (M74) using this system are ∼300 mg/kg. Here we describe the achievements and obstacles encountered during process development as well as characterization and stability of the purified Na-APR-1 (M74) protein and formulated vaccine. The expression, purification and analysis of purified Na-APR-1 (M74) protein obtained from representative 5 kg reproducibility runs performed to qualify the Na-APR-1 (M74) production process is also presented. This process has been successfully transferred to a pilot plant and a 50 kg scale manufacturing campaign under current Good Manufacturing Practice (cGMP) has been performed. The 50 kg run has provided a sufficient amount of protein to support the ongoing hookworm vaccine development program of the Sabin PDP. PMID:25905574

  3. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

    PubMed

    Lafferty, Diana J R; Laudenslager, Mark L; Mowat, Garth; Heard, Doug; Belant, Jerrold L

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.

  4. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

    PubMed

    Lafferty, Diana J R; Laudenslager, Mark L; Mowat, Garth; Heard, Doug; Belant, Jerrold L

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges. PMID:26529405

  5. Localization and characterization of neuropeptide Y-like peptides in the brain and islet organ of the anglerfish (Lophius americanus).

    PubMed

    Noe, B D; Milgram, S L; Balasubramaniam, A; Andrews, P C; Calka, J; McDonald, J K

    1989-08-01

    Results from a previous report demonstrate that more than one molecular form of neuropeptide Y-like peptide may be present in the islet organ of the anglerfish (Lophius americanus). Most of the neuropeptide Y-like immunoreactive material was anglerfish peptide YG, which is expressed in a subset of islet cells, whereas an additional neuropeptide Y-like peptide(s) was localized in islet nerves. To learn more about the neuropeptide Y-like peptides in islet nerves, we have employed immunohistochemical and biochemical methods to compare peptides found in anglerfish islets and brain. Using antisera that selectively react with either mammalian forms of neuropeptide Y or with anglerfish peptide YG, subsets of neurons were found in the brain that labelled with only one or the other of the antisera. In separate sections, other neurons that were labelled with either antiserum exhibited similar morphologies. Peptides from brains and islets were subjected to gel filtration and reverse-phase high performance liquid chromatography. Radioimmunoassays employing either the neuropeptide Y or peptide YG antisera were used to examine chromatographic eluates. Immunoreactive peptides having retention times of human neuropeptide Y and porcine neuropeptide Y were identified in extracts of both brain and islets. This indicates that peptides structurally similar to both of these peptides from the neuropeptide Y-pancreatic polypeptide family are expressed in neurons of anglerfish brain and nerve fibers of anglerfish islets. The predominant form of neuropeptide Y-like peptide in islets was anglerfish peptide YG. Neuropeptide Y-immunoreactive peptides from islet extracts that had chromatographic retention times identical to human neuropeptide Y and porcine neuropeptide Y were present in much smaller quantities.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2673525

  6. (Lack of) genetic diversity in immune genes predates glacial isolation in the North American mountain goat (Oreamnos americanus).

    PubMed

    Shafer, Aaron B A; Fan, Chia Wei; Côté, Steeve D; Coltman, David W

    2012-01-01

    The major histocompatibility complex (MHC) plays an important role in an organism's ability to respond to pathogens. Immunogenetic diversity is advantageous as it permits the recognition of more external antigens. For this reason, MHC and immune gene variation are considered a barometer for the genetic health of wild populations. Mountain goats (Oreamnos americanus) were previously shown to have little variation at the MHC Class II Oram-DRB locus, which was attributed to population bottlenecks during the last glacial maximum (LGM). In this paper, we extended the analysis of immunogenetic variability in mountain goats to 5 genes representing the 3 classes of MHC gene (Class I OLA, Class II DRA and DRB, and Class III TNF-α) and the natural resistance-associated macrophage protein. We sequenced approximately 3000 bp from 31 individuals sampled across the range of mountain goats and found very low levels of diversity (1-3 polymorphic sites per gene) with the exception of the Class I Oram-OLA gene. Oram-OLA was nearly 30 times more diverse than the other immune genes and appears to represent a source of increased immunogenetic diversity. This diversity may be attributed to multiple loci, mediated by pathogen exposure, or potentially influenced by social factors. The distribution of SNPs was not associated with refugial history, suggesting that the current distribution of immunogenetic diversity was present prior to the LGM. These data suggest that although they have low levels of diversity at the 4 of 5 immune loci, mountain goats may be better equipped for future climate oscillations and pathogen exposure than previously thought. PMID:22268162

  7. Transfer of benzo(a)pyrene from two invertebrate prey species to the winter flounder, Pleuronectes americanus

    SciTech Connect

    Schnitz, A.R.; Taghon, G.L.

    1995-12-31

    Anthropogenic activities in and around the estuarine environment may introduce compounds with the ability to move through trophic levels, resulting in adverse effects to ecosystems and human health. In order to observe the potential for transfer of the carcinogen benzo(a)pyrene (BaP) and its derivatives from prey organisms to a predator, a simplified benthic food chain was constructed. Winter flounder, Pleuronectes americanus, were fed via gavage either softshell clams, Mya arenaria, or sandworms, Neanthes virens, that had previously been exposed to {sup 14}C-benzo(a)pyrene-contaminated sediments and contained 5.05 ng/g and 5.8 ng/g activity, respectively (wet weight). The fish received doses every 48 hours for a total of 192 hours after which time, all tissues except the gall bladder were examined for the presence of BaP using liquid scintillation spectrometry (LSC). The bile was extracted with chloroform/methanol and analyzed via high performance liquid chromatography (HPLC) and LSC. The flounders that were fed worms demonstrated increased metabolism of the PAH relative to those fed clams, as shown by higher concentrations of polar metabolites in the bile. This corresponds with the higher concentration of metabolites recovered in the worm tissue; more than 95% of the recovered activity was in the form of polar derivatives whereas the activity in the clam tissue was almost completely parent benzo(a)pyrene. As was expected, the BaP metabolites formed by the fish were mediated by the differing abilities of the prey species to derivatize the PAH. Thus, macrofaunal interactions with sedimentary-associated polycyclic aromatic hydrocarbons may be important determinants in the fate and transport of these compounds in the benthos.

  8. Kinematics, hydrodynamics and force production of pleopods suggest jet-assisted walking in the American lobster (Homarus americanus).

    PubMed

    Lim, Jeanette L; Demont, M Edwin

    2009-09-01

    The American lobster (Homarus americanus) displays a diverse set of locomotory behaviours that includes tail flips, walking and paddling. Paddling is carried out by the four pairs of paddle-shaped pleopods on the ventral abdomen. Although it is recognized that pleopod-generated fluid flows have some locomotory role in adults, reports on their relative importance in locomotion are inconsistent. This paper integrates experimental kinematics and hydrodynamics of lobster pleopod beating to determine the mechanism and magnitude of pleopod force production. A kinematic analysis of pleopod beating in live lobsters showed that the pleopods execute an adlocomotory metachronal beating pattern. We modelled in vivo pleopod kinematics with a set of simple trigonometric functions, and used these functions to program a mechanical lobster model consisting of motor-driven pleopods on a lobster abdomen exoskeleton. Based on flow visualizations obtained from applying particle image velocimetry to the lobster model, we propose that the unsteady metachronal kinematics of the pleopods can maximize thrust by exploiting forces arising from individual pleopod activity and interactions among adjacent pairs. The pleopods continuously entrain fluid surrounding the lobster and create a caudally directed fluid jet oriented parallel to the substratum. Inputting wake morphology and velocity data into a simplified model for steady jet thrust showed that the pleopods of the lobster model produced 27-54 mN of thrust, which is comparable to the propulsive forces generated by other proficient swimmers. These results suggest that lobster pleopods are capable of producing forces of a magnitude that could assist the walking legs in forward propulsion.

  9. Copper-metallothioneins in the American lobster, Homarus americanus: potential role as Cu(I) donors to apohemocyanin.

    PubMed Central

    Brouwer, M; Whaling, P; Engel, D W

    1986-01-01

    The physiological function of copper(I)-metallothionein is not well understood. The respiratory function of hemocyanin, a copper(I)-containing respiratory protein found in the hemolymph of many invertebrates, has been known a long time. However, the mechanism by which Cu(I) is inserted into the oxygen-binding site of apohemocyanin is completely unknown. This investigation tests the hypothesis that copper(I)-metallothionein may act as a Cu(I) donor to apohemocyanin. To this end, copper-binding proteins and hemocyanin were purified from the digestive gland and hemolymph of the American lobster, Homarus americanus. In the presence of beta-mercaptoethanol, the copper-binding proteins can be resolved into three components on DEAE-cellulose. The first two have been characterized as metallothioneins, based on their high cysteine content and lack of aromatic amino acid residues. The cysteine content of the third component is half of that of components I and II. In the absence of beta-mercaptoethanol the three proteins elute as a single protein complex during ion-exchange chromatography. Components I and II show a strong tendency to polymerize, a process that is accompanied by the loss of protein-bound copper. The purified proteins are not capable of transferring Cu(I) to the active sites of completely copper-free apohemocyanin. They are capable, however, of transferring Cu(I) to active sites of hemocyanin containing reduced amounts of Cu(I), suggesting that the conformational state of hemocyanin is the determining factor in the Cu(I) transfer mechanism. PMID:3709470

  10. (Lack of) genetic diversity in immune genes predates glacial isolation in the North American mountain goat (Oreamnos americanus).

    PubMed

    Shafer, Aaron B A; Fan, Chia Wei; Côté, Steeve D; Coltman, David W

    2012-01-01

    The major histocompatibility complex (MHC) plays an important role in an organism's ability to respond to pathogens. Immunogenetic diversity is advantageous as it permits the recognition of more external antigens. For this reason, MHC and immune gene variation are considered a barometer for the genetic health of wild populations. Mountain goats (Oreamnos americanus) were previously shown to have little variation at the MHC Class II Oram-DRB locus, which was attributed to population bottlenecks during the last glacial maximum (LGM). In this paper, we extended the analysis of immunogenetic variability in mountain goats to 5 genes representing the 3 classes of MHC gene (Class I OLA, Class II DRA and DRB, and Class III TNF-α) and the natural resistance-associated macrophage protein. We sequenced approximately 3000 bp from 31 individuals sampled across the range of mountain goats and found very low levels of diversity (1-3 polymorphic sites per gene) with the exception of the Class I Oram-OLA gene. Oram-OLA was nearly 30 times more diverse than the other immune genes and appears to represent a source of increased immunogenetic diversity. This diversity may be attributed to multiple loci, mediated by pathogen exposure, or potentially influenced by social factors. The distribution of SNPs was not associated with refugial history, suggesting that the current distribution of immunogenetic diversity was present prior to the LGM. These data suggest that although they have low levels of diversity at the 4 of 5 immune loci, mountain goats may be better equipped for future climate oscillations and pathogen exposure than previously thought.

  11. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus)

    PubMed Central

    Lafferty, Diana J. R.; Laudenslager, Mark L.; Mowat, Garth; Heard, Doug; Belant, Jerrold L.

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges. PMID:26529405

  12. Antihypertensive neutral lipid

    SciTech Connect

    Snyder, F.L.; Blank, M.L.

    1986-06-17

    A method is described for treating a warm-blooded animal comprising administering to the animal a neutral glycerolipid with a 12 to 20 carbon alkyl group at the sn-1 position, a short carbon chain acyl group at the sn-2 position and a hydroxyl group at the sn-3 position in an amount sufficient to lower the arterial blood pressure of the animal. A method is also described for treating a warm-blooded animal comprising administering a composition consisting essentially of a 1-alkyl-2-acetyl (or propionyl)-sn glycerol in combination with a 1-alkyl-2-acetyl-sn-glycero-3-phosphocholine, wherein the 1-alkyl groups contain 12 to 20 carbon atoms, dissolved in an inert pharmaceutically acceptable solvent in amounts sufficient to lower the arterial blood pressure of the animal.

  13. Multivariate analysis of human immunodeficiency virus type 1 neutralization data.

    PubMed Central

    Nyambi, P N; Nkengasong, J; Lewi, P; Andries, K; Janssens, W; Fransen, K; Heyndrickx, L; Piot, P; van der Groen, G

    1996-01-01

    We report on the use of spectral map analysis of the inter- and intraclade neutralization data of 14 sera of human immunodeficiency virus type 1 (HIV-1)-infected individuals and 16 primary isolates, representing genetic clades A to H in group M and group O. This multivariate analysis has been used previously to study the interaction between drugs and receptors and between viruses and antiviral compounds. The analysis reveals the existence of neutralization clusters, not correlated with the known genetic clades. The structural factors that have been identified may correlate with the most important neutralization epitopes. Three key primary HIV-1 isolates, which allow discrimination of sera that are likely or unlikely to neutralize primary isolates from most of the genetic clades, were identified. Our method of analysis will facilitate the evaluation as well as the design of suitable HIV-1 vaccines, which induce high-titer interclade cross-neutralizing antibodies. PMID:8709250

  14. Transient ion neutralization by electrons.

    NASA Technical Reports Server (NTRS)

    Wilhelm, H. E.

    1973-01-01

    The nonlinear initial-boundary-value problems describing the lateral neutralization of ion beams for the cases that (1) an auxiliary electric field accelerates the electrons into the ion space, and (2) the electrons are injected into the ion space at a prescribed current density are treated. Analytical solutions are derived which give the position and speed of the neutralization front as a function of time, and the temporal development of the electron density, velocity, and electric fields during the neutralization process.

  15. Chemistry of carotenoid neutral radicals.

    PubMed

    Ligia Focsan, A; Magyar, Adam; Kispert, Lowell D

    2015-04-15

    Proton loss from the carotenoid radical cations (Car(+)) to form neutral radicals (#Car) was investigated by numerous electrochemical, EPR, ENDOR and DFT studies described herein. The radical cation and neutral radicals were formed in solution electrochemically and stabilized on solid silica-alumina and MCM-41 matrices. Carotenoid neutral radicals were recently identified in Arabidopsis thaliana plant and photosystem II samples. Deprotonation at the terminal ends of a zeaxanthin radical cation could provide a secondary photoprotection pathway which involves quenching excited state chlorophyll by the long-lived zeaxanthin neutral radicals formed. PMID:25687648

  16. Constraining the Europa Neutral Torus

    NASA Astrophysics Data System (ADS)

    Smith, Howard T.; Mitchell, Donald; mauk, Barry; Johnson, Robert E.; clark, george

    2016-10-01

    "Neutral tori" consist of neutral particles that usually co-orbit along with their source forming a toroidal (or partial toroidal) feature around the planet. The distribution and composition of these features can often provide important, if not unique, insight into magnetospheric particles sources, mechanisms and dynamics. However, these features can often be difficult to directly detect. One innovative method for detecting neutral tori is by observing Energetic Neutral Atoms (ENAs) that are generally considered produced as a result of charge exchange interactions between charged and neutral particles.Mauk et al. (2003) reported the detection of a Europa neutral particle torus using ENA observations. The presence of a Europa torus has extremely large implications for upcoming missions to Jupiter as well as understanding possible activity at this moon and providing critical insight into what lies beneath the surface of this icy ocean world. However, ENAs can also be produced as a result of charge exchange interactions between two ionized particles and in that case cannot be used to infer the presence of neutral particle population. Thus, a detailed examination of all possible source interactions must be considered before one can confirm that likely original source population of these ENA images is actually a Europa neutral particle torus. For this talk, we examine the viability that the Mauk et al. (2003) observations were actually generated from a neutral torus emanating from Europa as opposed to charge particle interactions with plasma originating from Io. These results help constrain such a torus as well as Europa source processes.

  17. A proposed neutral line signature

    NASA Technical Reports Server (NTRS)

    Doxas, I.; Speiser, T. W.; Dusenbery, P. B.; Horton, W.

    1992-01-01

    An identifying signature is proposed for the existence and location of the neutral line in the magnetotail. The signature, abrupt density, and temperature changes in the Earthtail direction, was first discovered in test particle simulations. Such temperature variations have been observed in ISEE data (Huang et. al. 1992), but their connection to the possible existence of a neutral line in the tail has not yet been established. The proposed signature develops earlier than the ion velocity space ridge of Martin and Speiser (1988), but can only be seen by spacecraft in the vicinity of the neutral line, while the latter can locate a neutral line remotely.

  18. NEUTRAL-BEAM INJECTION

    SciTech Connect

    Kunkel, W.B.

    1980-06-01

    The emphasis in the preceding chapters has been on magnetic confinement of high temperature plasmas. The question of production and heating of such plasmas has been dealt with relatively more briefly. It should not be inferred, however, that these matters must therefore be either trivial or unimportant. A review of the history reveals that in the early days all these aspects of the controlled fusion problem were considered to be on a par, and were tackled simultaneously and with equal vigor. Only the confinement problem turned out to be much more complex than initially anticipated, and richer in challenge to the plasma physicist than the questions of plasma production and heating. On the other hand, the properties of high-temperature plasmas and plasma confinement can only be studied experimentally after the problems of production and of heating to adequate temperatures are solved. It is the purpose of this and the next chapter to supplement the preceding discussions with more detail on two important subjects: neutral-beam injection and radio-frequency heating. These are the major contenders for heating in present and future tokamak and mirror fusion experiments, and even in several proposed reactors. For neutral beams we emphasize here the technology involved, which has undergone a rather remarkable development. The physics of particle and energy deposition in the plasma, and the discussion of the resulting effects on the confined plasma, have been included in previous chapters, and some experimental results are quoted there. Other heating processes of relevance to fusion are mentioned elsewhere in this book, in connection with the experiments where they are used: i.e. ohmic heating, adiabatic compression heating, and alpha-particle heating in Chapter 3 by H.P. Furth; more ohmic heating in Chapter 7, and shock-implosion heating, laser heating, and relativistic-electron beam heating in Chapter 8, both by W. E. Quinn. These methods are relatively straightforward in

  19. CO2-neutral fuels

    NASA Astrophysics Data System (ADS)

    Goede, A. P. H.

    2015-08-01

    The need for storage of renewable energy (RE) generated by photovoltaic, concentrated solar and wind arises from the fact that supply and demand are ill-matched both geographically and temporarily. This already causes problems of overcapacity and grid congestion in countries where the fraction of RE exceeds the 20% level. A system approach is needed, which focusses not only on the energy source, but includes conversion, storage, transport, distribution, use and, last but not least, the recycling of waste. Furthermore, there is a need for more flexibility in the energy system, rather than relying on electrification, integration with other energy systems, for example the gas network, would yield a system less vulnerable to failure and better adapted to requirements. For example, long-term large-scale storage of electrical energy is limited by capacity, yet needed to cover weekly to seasonal demand. This limitation can be overcome by coupling the electricity net to the gas system, considering the fact that the Dutch gas network alone has a storage capacity of 552 TWh, sufficient to cover the entire EU energy demand for over a month. This lecture explores energy storage in chemicals bonds. The focus is on chemicals other than hydrogen, taking advantage of the higher volumetric energy density of hydrocarbons, in this case methane, which has an approximate 3.5 times higher volumetric energy density. More importantly, it allows the ready use of existing gas infrastructure for energy storage, transport and distribution. Intermittent wind electricity generated is converted into synthetic methane, the Power to Gas (P2G) scheme, by splitting feedstock CO2 and H2O into synthesis gas, a mixture of CO and H2. Syngas plays a central role in the synthesis of a range of hydrocarbon products, including methane, diesel and dimethyl ether. The splitting is accomplished by innovative means; plasmolysis and high-temperature solid oxygen electrolysis. A CO2-neutral fuel cycle is

  20. Emergence of structural patterns in neutral trophic networks.

    PubMed

    Canard, Elsa; Mouquet, Nicolas; Marescot, Lucile; Gaston, Kevin J; Gravel, Dominique; Mouillot, David

    2012-01-01

    Interaction networks are central elements of ecological systems and have very complex structures. Historically, much effort has focused on niche-mediated processes to explain these structures, while an emerging consensus posits that both niche and neutral mechanisms simultaneously shape many features of ecological communities. However, the study of interaction networks still lacks a comprehensive neutral theory. Here we present a neutral model of predator-prey interactions and analyze the structural characteristics of the simulated networks. We find that connectance values (complexity) and complexity-diversity relationships of neutral networks are close to those observed in empirical bipartite networks. High nestedness and low modularity values observed in neutral networks fall in the range of those from empirical antagonist bipartite networks. Our results suggest that, as an alternative to niche-mediated processes that induce incompatibility between species ("niche forbidden links"), neutral processes create "neutral forbidden links" due to uneven species abundance distributions and the low probability of interaction between rare species. Neutral trophic networks must be seen as the missing endpoint of a continuum from niche to purely stochastic approaches of community organization. PMID:22899987

  1. Neutral Buoyancy Simulator (NBS)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    This is a cutaway illustration of the Neutral Buoyancy Simulator (NBS) at the Marshall Space Flight Center (MSFC ). The MSFC NBS provided an excellent environment for testing hardware to examine how it would operate in space and for evaluating techniques for space construction and spacecraft servicing. Here, engineers, designers, and astronauts performed various tests to develop basic concepts, preliminary designs, final designs, and crew procedures. The NBS was constructed of welded steel with polyester-resin coating. The water tank was 75-feet (22.9- meters) in diameter, 40-feet (12.2-meters) deep, and held 1.32 million gallons of water. Since it opened for operation in 1968, the NBS had supported a number of successful space missions, such as the Skylab, Solar Maximum Mission Satellite, Marned Maneuvering Unit, Experimental Assembly of Structures in Extravehicular Activity/Assembly Concept for Construction of Erectable Space Structures (EASE/ACCESS), the Hubble Space Telescope, and the Space Station. The function of the MSFC NBS was moved to the larger simulator at the Johnson Space Center and is no longer operational.

  2. Europa's Neutral Gas Torus

    NASA Astrophysics Data System (ADS)

    Mauk, B. H.; Mitchell, D. G.; McEntire, R. W.; Paranicas, C. P.; Roelof, E. C.; Williams, D. J.; Krimigis, S. M.; Lagg, A.

    2004-05-01

    In-situ energetic ion measurements from the Galileo spacecraft and remote energetic neutral atom (ENA) images from the Cassini spacecraft have been previously interpreted as revealing an unexpectedly massive torus of gas co-orbiting with Jupiter's moon Europa (Lagg et al., 2003; Mauk et al., 2003). Here we report on the results of detailed modeling of the ENA emission process from the Europa regions. Updates to the distribution and composition of the trapped energetic ion populations are included in the models, as are considerations of the partitioning of the gas products into multiple atomic and molecular species. Comparisons between the models and the Cassini observations reveal a torus with a total gas content equal to (0.5 +/- 0.2) E34 atoms plus molecules. This value is higher than, but within a factor of 3 of, an estimate inferred from a prediction of gas densities derived from Voyager plasma measurements and modeling of the interaction between the plasmas and the gases assumed to be emanating from Europa (Schreier et al., 1993). Lagg, A., N. Krupp, J. Woch, and D. J. Williams, Geophys. Res. Lett., 30, DOI 10.1029/2003GL017214, 2003. Mauk, B. H., D. G. Mitchell, S. M. Krimigs, E. C. Roelof, and C. P. Paranicas, Nature, 241, 920, 2003. Schreier, S., A. Eviatar, V. M. Vasyliunas, and J. D. Richardson, J. Geophys. Res., 98, 21231, 1993.

  3. Post-Mating Interactions and Their Effects on Fitness of Female and Male Echinothrips americanus (Thysanoptera: Thripidae), a New Insect Pest in China

    PubMed Central

    Li, Xiao-Wei; Jiang, Hong-Xue; Zhang, Xiao-Chen; Shelton, Anthony M.; Feng, Ji-Nian

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species. PMID:24489956

  4. Neutralization tests on the SERT 2 spacecraft

    NASA Technical Reports Server (NTRS)

    Kerslake, W. R.; Domitz, S.

    1979-01-01

    Neutralization test data obtained on the SERT 2 spacecraft are presented. Tests included ion beam neutralization of a thruster by a close (normal design) neutralizer as well as by a distant (1 meter) neutralizer. Parameters affecting neutralization, such as neutralizer bias voltage, neutralizer anode voltage, local spacecraft plasma density, and solar array voltage configuration were varied and changes in plasma potentials were measured. A plasma model is presented as an approximation of observed results.

  5. Windowpane flounder (Scophthalmus aquosus) and winter flounder (Pseudopleuronectes americanus) responses to cold temperature extremes in a Northwest Atlantic estuary

    NASA Astrophysics Data System (ADS)

    Wilber, Dara H.; Clarke, Douglas G.; Alcoba, Catherine M.; Gallo, Jenine

    2016-01-01

    The effect of climate variability on flatfish includes not only the effects of warming on sensitive life history stages, but also impacts from more frequent or unseasonal extreme cold temperatures. Cold weather events can affect the overwintering capabilities of flatfish near their low temperature range limits. We examined the responses of two flatfish species, the thin-bodied windowpane (Scophthalmus aquosus) and cold-tolerant winter flounder (Pseudopleuronectes americanus), to variable winter temperatures in a Northwest Atlantic estuary using abundance and size data collected during a monitoring study, the Aquatic Biological Survey, conducted from 2002 to 2010. Winter and spring abundances of small (50 to 120 mm total length) juvenile windowpane were positively correlated with adult densities (spawning stock) and fall temperatures (thermal conditions experienced during post-settlement development for the fall-spawned cohort) of the previous year. Windowpane abundances in the estuary were significantly reduced and the smallest size class was nearly absent after several consecutive years with cold (minimum temperatures < 1 °C) winters. Interannual variation in winter flounder abundances was unrelated to the severity of winter temperatures. A Paulik diagram illustrates strong positive correlations between annual abundances of sequential winter flounder life history stages (egg, larval, Age-1 juvenile, and adult male) within the estuary, reflecting residency within the estuary through their first year of life. Temperature variables representing conditions during winter flounder larval and post-settlement development were not significant factors in multiple regression models exploring factors that affect juvenile abundances. Likewise, densities of predators known to consume winter flounder eggs and/or post-settlement juveniles were not significantly related to interannual variation in winter flounder juvenile abundances. Colder estuarine temperatures through the

  6. Neutral point detection by satellites. [magnetospheric neutral sheets

    NASA Technical Reports Server (NTRS)

    Schindler, K.; Ness, N. F.

    1974-01-01

    The concept of a neutral point depends on the physical phenomena described. The regions with B less than about 1 gamma detected by Schindler and Ness may be interpreted as neutral regions for the ion-tearing process. The assumption of the presence of a multiple neutral point structure (with temporal variations) is still the most promising interpretation of the Explorer 34 data. Alternatives suggested by Russell lead to difficulties. Nevertheless, the final answer can come only from multiple satellite systems. A 1-day displacement of the day count in the data discussed by Schindler and Ness is corrected.

  7. Impact of viral attachment factor expression on antibody-mediated neutralization of flaviviruses.

    PubMed

    Obara, Christopher J; Dowd, Kimberly A; Ledgerwood, Julie E; Pierson, Theodore C

    2013-03-01

    Neutralization of flaviviruses requires engagement of the virion by antibodies with a stoichiometry that exceeds a required threshold. Factors that modulate the number of antibodies bound to an individual virion when it contacts target cells impact neutralization potency. However, the contribution of cellular factors to the potency of neutralizing antibodies has not been explored systematically. Here we investigate the relationship between expression level of a viral attachment factor on cells and the neutralizing potency of antibodies. Analysis of the attachment factor DC-SIGNR on cells in neutralization studies failed to identify a correlation between DC-SIGNR expression and antibody-mediated protection. Furthermore, neutralization potency was equivalent on a novel Jurkat cell line induced to express DC-SIGNR at varying levels. Finally, blocking virus-attachment factor interactions had no impact on neutralization activity. Altogether, our studies suggest that cellular attachment factor expression is not a significant contributor to the potency of neutralizing antibodies to flaviviruses.

  8. Environmental neutralization of polonium-218

    SciTech Connect

    Goldstein, S.D.; Hopke, P.K.

    1985-01-01

    Previous work has indicated that two mechanisms of neutralization of the singly charged polonium ion exist. Charged Polonium-218 can be neutralized by reacting with oxygen to form a polonium oxide ion with a higher ionization potential than that of the polonium metal and then accepting an electron transferred from a lower ionization potential gas. In this present work, this mechanism has been verified by determining that the polonium oxide has an ionization potential in the range 10.35-10.53 eV. It was also previously reported that /sup 218/Po can be neutralized, in the absence of oxygen, by the scavenging of electrons by a trace gas such as water or nitrogen dioxide and their diffusion to the polonium ion. To verify this second neutralization mechanism, concentrations of nitrogen dioxide in nitrogen in the range of 50 ppb-1 ppm were examined for their ability to neutralize the polonium ion. Complete neutralization of /sup 218/Po was observed at nitrogen dioxide concentrations greater than 700 ppb. For concentrations below 700 ppb, the degree of neutralization was found to increase smoothly with the nitrogen dioxide concentration.

  9. Mechanism of Neutralization by the Broadly Neutralizing HIV-1 Monoclonal Antibody VRC01▿†

    PubMed Central

    Li, Yuxing; O'Dell, Sijy; Walker, Laura M.; Wu, Xueling; Guenaga, Javier; Feng, Yu; Schmidt, Stephen D.; McKee, Krisha; Louder, Mark K.; Ledgerwood, Julie E.; Graham, Barney S.; Haynes, Barton F.; Burton, Dennis R.; Wyatt, Richard T.; Mascola, John R.

    2011-01-01

    The structure of VRC01 in complex with the HIV-1 gp120 core reveals that this broadly neutralizing CD4 binding site (CD4bs) antibody partially mimics the interaction of the primary virus receptor, CD4, with gp120. Here, we extended the investigation of the VRC01-gp120 core interaction to the biologically relevant viral spike to better understand the mechanism of VRC01-mediated neutralization and to define viral elements associated with neutralization resistance. In contrast to the interaction of CD4 or the CD4bs monoclonal antibody (MAb) b12 with the HIV-1 envelope glycoprotein (Env), occlusion of the VRC01 epitope by quaternary constraints was not a major factor limiting neutralization. Mutagenesis studies indicated that VRC01 contacts within the gp120 loop D, the CD4 binding loop, and the V5 region were necessary for optimal VRC01 neutralization, as suggested by the crystal structure. In contrast to interactions with the soluble gp120 monomer, VRC01 interaction with the native viral spike did not occur in a CD4-like manner; VRC01 did not induce gp120 shedding from the Env spike or enhance gp41 membrane proximal external region (MPER)-directed antibody binding to the Env spike. Finally, VRC01 did not display significant reactivity with human antigens, boding well for potential in vivo applications. The data indicate that VRC01 interacts with gp120 in the context of the functional spike in a manner distinct from that of CD4. It achieves potent neutralization by precisely targeting the CD4bs without requiring alterations of Env spike configuration and by avoiding steric constraints imposed by the quaternary structure of the functional Env spike. PMID:21715490

  10. Positional nystagmus showing neutral points.

    PubMed

    Hiruma, Kiyoshi; Numata, Tsutomu

    2004-01-01

    We encountered patients who had their static direction-changing positional nystagmus canceled at about 20-30 degrees yaw head rotation from the supine position. This nystagmus was also canceled when the head was rotated 180 degrees from this position. We call these head positions neutral points. At the neutral points, the cupula of the horizontal semicircular canal of the affected ear is positioned vertical to the gravitational plane and no deflection of the cupula occurs. The positional nystagmus observed (except the neutral points) was thought to occur due to a "heavy cupula" or "light cupula", which may be determined by the specific gravity of its endolymph.

  11. Neutral current interactions in MINOS

    SciTech Connect

    Sousa, Alexandre; /Oxford U.

    2007-07-01

    The Main Injector Neutrino Oscillation Search (MINOS) long-baseline experiment has been actively collecting beam data since 2005, having already accumulated 3 x 10{sup 20} protons-on-target (POT). The several million neutrinos per year observed at the Near detector may improve the existing body of knowledge of neutrino cross-sections and the Near-Far comparison of the observed energy spectrum neutral current events constrains oscillations into sterile neutrinos. MINOS capabilities of observing neutral current neutrino events are described and the employed methodology for event selection is discussed, along with preliminary results obtained. An outlook on the expected neutral current related contributions from MINOS is also presented.

  12. [Neutral Medical Claim Management Committee].

    PubMed

    Komatsu, Mitsuru

    2013-03-01

    The Ibaraki Medical Association established the Committee for Alternative Dispute Resolution called the Neutral Medical Claim Management Committee in 2006. Among 64 claims presented to the committee, 29 were settled through mediation or consultation. Patients were generally satisfied that their claims were considered fairly by the committee and that they were able to talk directly with healthcare professionals. However, some did not consider the committee to be completely neutral. The healthcare professionals involved rated the committee highly because they felt that the processes were neutral and no emotional aspects were involved. PMID:23617190

  13. Atomic Transition Probabilities for Neutral Cerium

    NASA Astrophysics Data System (ADS)

    Lawler, J. E.; den Hartog, E. A.; Wood, M. P.; Nitz, D. E.; Chisholm, J.; Sobeck, J.

    2009-10-01

    The spectra of neutral cerium (Ce I) and singly ionized cerium (Ce II) are more complex than spectra of other rare earth species. The resulting high density of lines in the visible makes Ce ideal for use in metal halide (MH) High Intensity Discharge (HID) lamps. Inclusion of cerium-iodide in a lamp dose can improve both the Color Rendering Index and luminous efficacy of a MH-HID lamp. Basic spectroscopic data including absolute atomic transition probabilities for Ce I and Ce II are needed for diagnosing and modeling these MH-HID lamps. Recent work on Ce II [1] is now being augmented with similar work on Ce I. Radiative lifetimes from laser induced fluorescence measurements [2] on neutral Ce are being combined with emission branching fractions from spectra recorded using a Fourier transform spectrometer. A total of 14 high resolution spectra are being analyzed to determine branching fractions for 2000 to 3000 lines from 153 upper levels in neutral Ce. Representative data samples and progress to date will be presented. [4pt] [1] J. E. Lawler, C. Sneden, J. J. Cowan, I. I. Ivans, and E. A. Den Hartog, Astrophys. J. Suppl. Ser. 182, 51-79 (2009). [0pt] [2] E. A. Den Hartog, K. P. Buettner, and J. E. Lawler, J. Phys. B: Atomic, Molecular & Optical Physics 42, 085006 (7pp) (2009).

  14. Incomplete Neutralization and Deviation from Sigmoidal Neutralization Curves for HIV Broadly Neutralizing Monoclonal Antibodies.

    PubMed

    McCoy, Laura E; Falkowska, Emilia; Doores, Katie J; Le, Khoa; Sok, Devin; van Gils, Marit J; Euler, Zelda; Burger, Judith A; Seaman, Michael S; Sanders, Rogier W; Schuitemaker, Hanneke; Poignard, Pascal; Wrin, Terri; Burton, Dennis R

    2015-08-01

    The broadly neutralizing HIV monoclonal antibodies (bnMAbs) PG9, PG16, PGT151, and PGT152 have been shown earlier to occasionally display an unusual virus neutralization profile with a non-sigmoidal slope and a plateau at <100% neutralization. In the current study, we were interested in determining the extent of non-sigmoidal slopes and plateaus at <100% for HIV bnMAbs more generally. Using both a 278 panel of pseudoviruses in a CD4 T-cell (U87.CCR5.CXCR4) assay and a panel of 117 viruses in the TZM-bl assay, we found that bnMAbs targeting many neutralizing epitopes of the spike had neutralization profiles for at least one virus that plateaued at <90%. Across both panels the bnMAbs targeting the V2 apex of Env and gp41 were most likely to show neutralization curves that plateaued <100%. Conversely, bnMAbs targeting the high-mannose patch epitopes were less likely to show such behavior. Two CD4 binding site (CD4bs) Abs also showed this behavior relatively infrequently. The phenomenon of incomplete neutralization was also observed in a large peripheral blood mononuclear cells (PBMC)-grown molecular virus clone panel derived from patient viral swarms. In addition, five bnMAbs were compared against an 18-virus panel of molecular clones produced in 293T cells and PBMCs and assayed in TZM-bl cells. Examples of plateaus <90% were seen with both types of virus production with no consistent patterns observed. In conclusion, incomplete neutralization and non-sigmoidal neutralization curves are possible for all HIV bnMAbs against a wide range of viruses produced and assayed in both cell lines and primary cells with implications for the use of antibodies in therapy and as tools for vaccine design. PMID:26267277

  15. Incomplete Neutralization and Deviation from Sigmoidal Neutralization Curves for HIV Broadly Neutralizing Monoclonal Antibodies.

    PubMed

    McCoy, Laura E; Falkowska, Emilia; Doores, Katie J; Le, Khoa; Sok, Devin; van Gils, Marit J; Euler, Zelda; Burger, Judith A; Seaman, Michael S; Sanders, Rogier W; Schuitemaker, Hanneke; Poignard, Pascal; Wrin, Terri; Burton, Dennis R

    2015-08-01

    The broadly neutralizing HIV monoclonal antibodies (bnMAbs) PG9, PG16, PGT151, and PGT152 have been shown earlier to occasionally display an unusual virus neutralization profile with a non-sigmoidal slope and a plateau at <100% neutralization. In the current study, we were interested in determining the extent of non-sigmoidal slopes and plateaus at <100% for HIV bnMAbs more generally. Using both a 278 panel of pseudoviruses in a CD4 T-cell (U87.CCR5.CXCR4) assay and a panel of 117 viruses in the TZM-bl assay, we found that bnMAbs targeting many neutralizing epitopes of the spike had neutralization profiles for at least one virus that plateaued at <90%. Across both panels the bnMAbs targeting the V2 apex of Env and gp41 were most likely to show neutralization curves that plateaued <100%. Conversely, bnMAbs targeting the high-mannose patch epitopes were less likely to show such behavior. Two CD4 binding site (CD4bs) Abs also showed this behavior relatively infrequently. The phenomenon of incomplete neutralization was also observed in a large peripheral blood mononuclear cells (PBMC)-grown molecular virus clone panel derived from patient viral swarms. In addition, five bnMAbs were compared against an 18-virus panel of molecular clones produced in 293T cells and PBMCs and assayed in TZM-bl cells. Examples of plateaus <90% were seen with both types of virus production with no consistent patterns observed. In conclusion, incomplete neutralization and non-sigmoidal neutralization curves are possible for all HIV bnMAbs against a wide range of viruses produced and assayed in both cell lines and primary cells with implications for the use of antibodies in therapy and as tools for vaccine design.

  16. Neutralization of HIV by Milk Expressed Antibody

    PubMed Central

    Yu, Xiaocong; Pollock, Daniel; Duval, Mark; Lewis, Christopher; Joseph, Kristin; Meade, Harry; Cavacini, Lisa

    2012-01-01

    Background In some areas of the world mother-to-child transmission of HIV remains a significant problem in part due to widespread breastfeeding which is essential due to scarce supply of a safe replacement, protection conferred by breast milk against many enteric illnesses, and cultural norms. We propose that sustained, adequate levels of protective antibodies in breast milk will prevent transmission of HIV. Methods The HIV neutralizing human monoclonal antibody b12 (IgG1) has been expressed as an IgA2 in CHO cells and shown to retain full immunoreactivity and neutralizing activity as the parental IgG1. The expression plasmids containing the b12 heavy and light chains were also used to construct milk specific expression vectors using the GTC goat β-casein expression vector to direct expression of linked genes to the mammary gland with subsequent secretion into the milk. Female transgenic mice were generated and following parturition, their milk was tested for antibody immunoreactivity with gp120 and neutralization of HIV. Results When compared to CHO derived b12 IgA2 (or IgG1), immunoreactivity was retained. When tested for neutralization, milk derived b12 IgA2 was at least comparable to CHO derived antibody and in some cases superior to CHO derived antibody. Furthermore, milk that expressed b12 IgA2 was significantly more effective at mediating antibody dependent cell killing. Conclusions These results suggest it is possible to achieve functional HIV-specific mAb in the milk of transgenic mice and further investigations are warranted to explore ways for inducing this type of antibody response in the breast milk of HIV infected women. PMID:23269241

  17. Isolation and genetic characterization of Toxoplasma gondii from raccoons (Procyon lotor), cats (Felis domesticus), striped skunk (Mephitis mephitis), black bear (Ursus americanus), and cougar (Puma concolor) from Canada.

    PubMed

    Dubey, J P; Quirk, T; Pittt, J A; Sundar, N; Velmurugan, G V; Kwok, O C H; Leclair, D; Hill, R; Su, C

    2008-02-01

    Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats (Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus) from Kuujjuaq, northern Quebec, Canada. Genotyping of these T. gondii isolates using polymorphisms at 10 nuclear markers including SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico revealed 4 genotypes. None of the isolates was clonal archetypal Types I, II, and III found in the United States. These results are in contrast with the Type II genotype that is widespread in domestic animals and humans throughout the United States and Europe. This is the first genotyping of T. gondii isolates from this part of North America.

  18. Triplex polymerase chain reaction assay for detection of major soil-transmitted helminths, Ascaris lumbricoides, Trichuris trichiura, Necator americanus, in fecal samples.

    PubMed

    Phuphisut, Orawan; Yoonuan, Tippayarat; Sanguankiat, Surapol; Chaisiri, Kittipong; Maipanich, Wanna; Pubampen, Somchit; Komalamisra, Chalit; Adisakwattana, Poom

    2014-03-01

    Ascaris lumbricoides, Trichuris trichiura, and Necator americanus are medically important soil-transmitted helminths (STHs) occurring frequently worldwide including Thailand. Fecal examination using a microscope has been recommended as the gold standard for diagnosis of STH infections, but suffers from low sensitivity. Recently, highly sensitive and specific assays, such as multiplex quantitative PCR, has been established, but the high cost and need for special instruments are still barriers limiting their applications in routine diagnosis. Therefore, a conventional multiplex PCR assay, with its lower cost and greater simplicity, was developed, for the simultaneous detection of STHs in fecal samples. The multiplex PCR assay was species-specific to the three STHs, and could detect one copy of DNA target. Compared with microscopic examination of fecal samples, sensitivity and specificity of the multiplex PCR was 87% and 83%, respectively. This multiplex PCR assay provides an alternative method for routine diagnosis of STHs infection, and might be applied for epidemiological studies of STHs in endemic areas.

  19. Structural and mechanical properties of the arthropod cuticle: comparison between the fang of the spider Cupiennius salei and the carapace of American lobster Homarus americanus.

    PubMed

    Erko, Maxim; Hartmann, Markus A; Zlotnikov, Igor; Valverde Serrano, Clara; Fratzl, Peter; Politi, Yael

    2013-08-01

    Most biological materials are nanocomposites characterized by a multi-level structural hierarchy. Particularly, the arthropod cuticle is a chitin-based composite material where the mechanical properties strongly depend on both molecular chitin/protein properties, and the structural arrangement of chitin-fibrils within the protein matrix. Here materials properties and structural organization of two types of cuticle from distantly related arthropods, the wandering spider Cupiennius salei and American lobster Homarus americanus were studied using nanoindentation and X-ray diffraction. The structural analysis of the two types of cuticle including the packing and alignment of chitin-fibrils is supported by Monte Carlo simulations of the experimental X-ray data, thereby regions of parallel and rotated fibril arrangement can be clearly distinguished. The tip of the spider fang which is used to inject venom into the prey was found to be considerably harder than the lobster carapace, while its stiffness is slightly lower. PMID:23765087

  20. Sequence conservation in the Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) from hookworm infected individuals in Thailand.

    PubMed

    Ungcharoensuk, Charoenchai; Putaporntip, Chaturong; Pattanawong, Urassaya; Jongwutiwes, Somchai

    2012-12-01

    The Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. To elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the Na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of Thailand. Sequence analysis revealed that the gene encoding Na-ASP-2 comprised 8 exons. Of 3 nucleotide substitutions in these exons, only one causes an amino acid change from leucine to methionine. A consensus conserved GT and AG at the 5' and the 3' boundaries of each intron was observed akin to those found in other eukaryotic genes. Introns of Na-asp-2 contained 23 nucleotide substitutions and 0-18 indels. The mean number of nucleotide substitutions per site (d) in introns was not significantly different from the mean number of synonymous substitutions per synonymous site (d(S)) in exons whereas d in introns was significantly exceeded d(N) (the mean number of nonsynonymous substitutions per nonsynonymous site) in exons (p<0.05), suggesting that introns and synonymous sites in exons may evolve at a similar rate whereas functional constraints at the amino acid could limit amino acid substitutions in Na-ASP-2. A recombination site was identified in an intron near the 3' portion of the gene. The positions of introns and the intron phases in the Na-asp-2 gene comparing with those in other pathogenesis-related-1 proteins of Loa loa, Onchocerca volvulus, Heterodera glycines, Caenorhabditis elegans and human were relatively conserved, suggesting evolutionary conservation of these genes. Sequence conservation in Na-ASP-2 may not compromise further vaccine design if adverse vaccine effects could be resolved whereas microheterogeneity in introns of this locus may be useful for population genetics analysis of N. americanus

  1. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    SciTech Connect

    Asojo, Oluwatoyin A.; Loukas, Alex; Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M.; Hotez, Peter J.

    2005-04-01

    In order to clarify the structural basis of the pathogenesis-related-1 domain, Na-ASP-1, the first multi-domain ASP from the human hookworm parasite N. americanus, has been crystallized. 2.2 Å resolution data have been collected from a crystal belonging to the monoclinic space group P2{sub 1}. Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P2{sub 1} with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit.

  2. Sequence conservation in the Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) from hookworm infected individuals in Thailand.

    PubMed

    Ungcharoensuk, Charoenchai; Putaporntip, Chaturong; Pattanawong, Urassaya; Jongwutiwes, Somchai

    2012-12-01

    The Ancylostoma secreted protein-2 of Necator americanus (Na-ASP-2) was one of the promising vaccine candidates against the most prevalent human hookworm species as adverse vaccine reaction has compromised further human vaccine trials. To elucidate the gene structure and the extent of sequence diversity, we determined the complete nucleotide sequence of the Na-asp-2 gene of individual larvae from 32 infected subjects living in 3 different endemic areas of Thailand. Sequence analysis revealed that the gene encoding Na-ASP-2 comprised 8 exons. Of 3 nucleotide substitutions in these exons, only one causes an amino acid change from leucine to methionine. A consensus conserved GT and AG at the 5' and the 3' boundaries of each intron was observed akin to those found in other eukaryotic genes. Introns of Na-asp-2 contained 23 nucleotide substitutions and 0-18 indels. The mean number of nucleotide substitutions per site (d) in introns was not significantly different from the mean number of synonymous substitutions per synonymous site (d(S)) in exons whereas d in introns was significantly exceeded d(N) (the mean number of nonsynonymous substitutions per nonsynonymous site) in exons (p<0.05), suggesting that introns and synonymous sites in exons may evolve at a similar rate whereas functional constraints at the amino acid could limit amino acid substitutions in Na-ASP-2. A recombination site was identified in an intron near the 3' portion of the gene. The positions of introns and the intron phases in the Na-asp-2 gene comparing with those in other pathogenesis-related-1 proteins of Loa loa, Onchocerca volvulus, Heterodera glycines, Caenorhabditis elegans and human were relatively conserved, suggesting evolutionary conservation of these genes. Sequence conservation in Na-ASP-2 may not compromise further vaccine design if adverse vaccine effects could be resolved whereas microheterogeneity in introns of this locus may be useful for population genetics analysis of N. americanus.

  3. Identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the American lobster, Homarus americanus, cardiac neuromuscular system.

    PubMed

    Christie, A E; Stevens, J S; Bowers, M R; Chapline, M C; Jensen, D A; Schegg, K M; Goldwaser, J; Kwiatkowski, M A; Pleasant, T K; Shoenfeld, L; Tempest, L K; Williams, C R; Wiwatpanit, T; Smith, C M; Beale, K M; Towle, D W; Schooley, D A; Dickinson, P S

    2010-01-01

    In insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. Here, we show that a member of the insect calcitonin-like diuretic hormone (CLDH) family is present in the American lobster, Homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. Specifically, during an ongoing EST project, a transcript encoding a putative H. americanus CLDH precursor was identified; a full-length cDNA was subsequently cloned. In silico analyses of the deduced prepro-hormone predicted the mature structure of the encoded CLDH to be GLDLGLGRGFSGSQAAKHLMGLAAANFAGGPamide (Homam-CLDH), which is identical to a known Tribolium castaneum peptide. RT-PCR tissue profiling suggests that Homam-CLDH is broadly distributed within the lobster nervous system, including the cardiac ganglion (CG), which controls the movement of the neurogenic heart. RT-PCR analysis conducted on pacemaker neuron- and motor neuron-specific cDNAs suggests that the motor neurons are the source of the CLDH message in the CG. Perfusion of Homam-CLDH through the isolated lobster heart produced dose-dependent increases in both contraction frequency and amplitude and a dose-dependent decrease in contraction duration, with threshold concentrations for all parameters in the range 10(-11) to 10(-10) mol l(-1) or less, among the lowest for any peptide on this system. This report is the first documentation of a decapod CLDH, the first demonstration of CLDH bioactivity outside the Insecta, and the first detection of an intrinsic neuropeptide transcript in the crustacean CG. PMID:20008368

  4. Identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the American lobster, Homarus americanus, cardiac neuromuscular system

    PubMed Central

    Christie, A. E.; Stevens, J. S.; Bowers, M. R.; Chapline, M. C.; Jensen, D. A.; Schegg, K. M.; Goldwaser, J.; Kwiatkowski, M. A.; Pleasant, T. K.; Shoenfeld, L.; Tempest, L. K.; Williams, C. R.; Wiwatpanit, T.; Smith, C. M.; Beale, K. M.; Towle, D. W.; Schooley, D. A.; Dickinson, P. S.

    2010-01-01

    In insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. Here, we show that a member of the insect calcitonin-like diuretic hormone (CLDH) family is present in the American lobster, Homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. Specifically, during an ongoing EST project, a transcript encoding a putative H. americanus CLDH precursor was identified; a full-length cDNA was subsequently cloned. In silico analyses of the deduced prepro-hormone predicted the mature structure of the encoded CLDH to be GLDLGLGRGFSGSQAAKHLMGLAAANFAGGPamide (Homam-CLDH), which is identical to a known Tribolium castaneum peptide. RT-PCR tissue profiling suggests that Homam-CLDH is broadly distributed within the lobster nervous system, including the cardiac ganglion (CG), which controls the movement of the neurogenic heart. RT-PCR analysis conducted on pacemaker neuron- and motor neuron-specific cDNAs suggests that the motor neurons are the source of the CLDH message in the CG. Perfusion of Homam-CLDH through the isolated lobster heart produced dose-dependent increases in both contraction frequency and amplitude and a dose-dependent decrease in contraction duration, with threshold concentrations for all parameters in the range 10–11 to 10–10 mol l–1 or less, among the lowest for any peptide on this system. This report is the first documentation of a decapod CLDH, the first demonstration of CLDH bioactivity outside the Insecta, and the first detection of an intrinsic neuropeptide transcript in the crustacean CG. PMID:20008368

  5. Neutral and Non-Neutral Evolution of Drosophila Mitochondrial DNA

    PubMed Central

    Rand, D. M.; Dorfsman, M.; Kann, L. M.

    1994-01-01

    To test hypotheses of neutral evolution of mitochondrial DNA (mtDNA), nucleotide sequences were determined for 1515 base pairs of the NADH dehydrogenase subunit 5 (ND5) gene in the mitochondrial DNA of 29 lines of Drosophila melanogaster and 9 lines of its sibling species Drosophila simulans. In contrast to the patterns for nuclear genes, where D. melanogaster generally exhibits much less nucleotide polymorphism, the number of segregating sites was slightly higher in a global sample of nine ND5 sequences in D. melanogaster (s = 8) than in the nine lines of D. simulans (s = 6). When compared to variation at nuclear loci, the mtDNA variation in D. melanogaster does not depart from neutral expectations. The ND5 sequences in D. simulans, however, show fewer than half the number of variable sites expected under neutrality when compared to sequences from the period locus. While this reduction in variation is not significant at the 5% level, HKA tests with published restriction data for mtDNA in D. simulans do show a significant reduction of variation suggesting a selective sweep of variation in the mtDNA in this species. Tests of neutral evolution based on the ratios of synonymous and replacement polymorphism and divergence are generally consistent with neutral expectations, although a significant excess of amino acid polymorphism within both species is localized in one region of the protein. The rate of mtDNA evolution has been faster in D. melanogaster than in D. simulans and the population structure of mtDNA is distinct in these species. The data reveal how different rates of mtDNA evolution between species and different histories of neutral and adaptive evolution within species can compromise historical inferences in population and evolutionary biology. PMID:7851771

  6. Energetic Neutral Atom Precipitation (ENAP)

    NASA Technical Reports Server (NTRS)

    Tinsley, B. A.

    1988-01-01

    The Energetic Neutral Atom Precipitation experiment is scheduled to be flown on the Atmospheric Laboratory for Applications and Science (ATLAS 1) NASA mission. The objective of this experiment is to measure very faint emissions at nighttime arising from fluxes of energetic neutral atoms in the thermosphere. These energetic atoms have energies ranging up to about 50 keV, and arise from ions of hydrogen, helium, and oxygen trapped in the inner magnetosphere. Some of these ions become neutralized in charge exchange reactions with neutral hydrogen in the hydrogen geocorona that extends through the region. The ions are trapped on magnetic field lines which cross the equatorial plane at 2 to 6 earth radii distance, and they mirror at a range of heights on these field lines, extending down to the thermosphere at 500 km altitude. The ATLAS 1 measurements will not be of the neutral atoms themselves but of the optical emission produced by those on trajectories that intersect the thermosphere. The ENAP measurements are to be made using the Imaging Spectrometric Observatory (ISO) which is being flown on the ATLAS mission primarily for daytime spectral observations, and the ENAP measurements will all be nighttime measurements because of the faintness of the emissions and the relatively low level of magnetic activity expected.

  7. 46 CFR 502.404 - Neutrals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... resolution proceeding. A neutral shall have no official, financial, or personal conflict of interest with... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  8. 46 CFR 502.404 - Neutrals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... resolution proceeding. A neutral shall have no official, financial, or personal conflict of interest with... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  9. 46 CFR 502.404 - Neutrals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... resolution proceeding. A neutral shall have no official, financial, or personal conflict of interest with... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  10. 46 CFR 502.404 - Neutrals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... resolution proceeding. A neutral shall have no official, financial, or personal conflict of interest with... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  11. 46 CFR 502.404 - Neutrals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... resolution proceeding. A neutral shall have no official, financial, or personal conflict of interest with... Dispute Resolution § 502.404 Neutrals. (a) A neutral may be a permanent or temporary officer or employee... Maritime Commission Dispute Resolution Specialist will seek to provide a neutral in dispute...

  12. A Re-Examiniation of Phonological Neutralization.

    ERIC Educational Resources Information Center

    Dinnsen, D.

    1985-01-01

    Reviews research studies that raise serious questions about phonological neutralization, that is, the merger of a contrast in certain contexts. Some findings cast doubt on the very existence of neutralization and the correctness of the theoretical principles that make assumptions based on neutralization. Reanalyzes neutralization in light of these…

  13. PDX neutral beam reionization losses

    SciTech Connect

    Kugel, H.W.; Dylla, H.F.; Eubank, H.P.; Kozub, T.A.; Moore, R.; Schilling, G.; Stuart, L.D.; Von Halle, A.; Williams, M.D.

    1982-04-01

    Reionization losses for 1.5 MW H /sup 0/ and 2 MW D /sup 0/ neutral beams injected into the PDX tokamak were studied using pressure gauges, phototransistors, thermocouples, surface shielding, and surface sample analysis. Considerable outgassing of conventionally prepared 304 SS ducts occurred during initial injections and gradually decreased with the cumulative absorption of beam power. Reionization power losses are presently about 5% in the ducts and about 12% total for a beamline including the duct. Present duct pressures are attributed primarily to gas from the ion source and neutralizer with much smaller contributions from residual wall desorption. Physical mechanisms for the observed duct outgassing are discussed.

  14. ATF neutral beam injection system

    SciTech Connect

    Menon, M.M.; Morris, R.N.; Edmonds, P.H.

    1985-01-01

    The Advanced Toroidal Facility is a stellarator torsatron being built at Oak Ridge National Laboratory to investigate improved plasma confinement schemes. Plasmas heating will be carried out predominantly by means of neutral beam injection. This paper describes the basic parameters of the injection system. Numerical calculations were done to optimize the aiming of the injectors. The results of these calculations and their implications on the neutral power to the machine are elaborated. The effects of improving the beam optics and altering the focal length on the power transmitted to the plasma are discussed.

  15. Early appearance of neutralizing antibodies after vaccination with an inactivated hepatitis A vaccine.

    PubMed

    Flehmig, B; Staedele, H; Xueref, C; Vidor, E; Zuckerman, J; Zuckerman, A

    1997-07-01

    Sera from 30 subjects vaccinated with the Pasteur Merieux Serums & Vaccins (PM) inactivated hepatitis A vaccine, and from 30 subjects vaccinated with the Smithkline Beecham (SB) inactivated hepatitis A vaccine, were tested in two laboratories in order to provide comparative data on neutralizing activities of vaccine-induced antibodies. Sera were also evaluated by a modified radioimmunoassay (mRIA) and results were compared to neutralization assays results. Neutralizing antibody titres provided by the two laboratories correlated well (coefficient or correlation 0.42, P < 0.001). Neutralizing antibodies were detected after vaccination with both vaccines, and the kinetics of neutralizing antibody were the same with both vaccines. The titres gradually increased between the second week after the first dose and the post-booster dose (week 28). A strong booster effect of the booster vaccine dose on neutralizing titres was observed. Significantly higher neutralizing antibody titres with the PM vaccine were observed as early immune response on week 2 titres on both series of results. Vaccine-induced neutralizing antibody titres and vaccine-induced antibody mRIA titres correlated well (coefficient of correlation 0.82 and 0.72, respectively, P < 0.0001 in both cases). These results demonstrate early appearance of neutralizing antibody at high titre with the PM vaccine.

  16. Monoclonal antibody analysis of neutralization and antibody-dependent enhancement of feline infectious peritonitis virus.

    PubMed

    Corapi, W V; Olsen, C W; Scott, F W

    1992-11-01

    Fifty-four monoclonal antibodies (MAbs) to feline infectious peritonitis virus (FIPV) were characterized according to protein specificity, immunoglobulin subclass, virus neutralization, reactivity with different coronaviruses, and ability to induce antibody-dependent enhancement (ADE) of FIPV infection in vitro. The MAbs were found to be specific for one of three structural proteins of FIPV. A total of 47 MAbs were specific for the 205-kDa spike protein (S), 3 MAbs were specific for the 45-kDa nucleocapsid protein (N), and 4 MAbs were specific for the 26- to 28-kDa membrane protein (M). The S-specific MAbs showed various degrees of cross-reactivity with strains of FIPV, feline enteric coronavirus, canine coronavirus, and porcine transmissible gastroenteritis virus. Nineteen S-specific MAbs neutralized FIPV. A total of 15 of the neutralizing MAbs induced ADE, and all but 1 were of the immunoglobulin G2a subclass. The remaining four neutralizing MAbs that did not induce ADE were of the immunoglobulin G1 subclass. Two S-specific MAbs induced ADE but were nonneutralizing. None of the N- or M-specific MAbs was neutralizing or induced ADE. On the basis of the reactivity patterns of the MAbs with FIPV and related coronaviruses, it was concluded that there is a minimum of five neutralizing sites on S. In most instances, neutralizing MAbs were able to induce ADE, demonstrating a direct relationship between neutralization and enhancement. The difference in immunoglobulin subclass between neutralizing MAbs that induced ADE and those that did not induce ADE suggests that there may be a restriction in the immunoglobulin subclasses capable of mediating ADE.

  17. MSFC Skylab neutral buoyancy simulator

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The use of a neutral buoyancy simulator for developing extravehicular activity systems and for training astronauts in weightless activities is discussed. The construction of the facility and the operations are described. The types of tests and the training activities conducted in the simulator are reported. Photographs of the components of the simulator and actual training exercises are included.

  18. RE: Pedagogy--After Neutrality

    ERIC Educational Resources Information Center

    I'Anson, John

    2010-01-01

    Within the UK and in many parts of the world, official accounts of what it is to make sense of religion are framed within a rhetorics of neutrality in which such study is premised upon the possibility of dispassionate engagement and analysis. This paper, which is largely theoretical in scope, explores both the affordances and the costs of such an…

  19. Self-neutralized ion beam

    SciTech Connect

    Salvadori, M. C.; Teixeira, F. S.; Nikolaev, A.; Savkin, K. P.; Oks, E. M.; Spaedtke, P.; Yu, K. M.; Brown, I. G.

    2011-10-15

    A vacuum arc ion source provides high current beams of metal ions that have been used both for accelerator injection and for ion implantation, and in both of these applications the degree of space charge neutralization of the beam is important. In accelerator injection application, the beam from the ion source may be accelerated further (post-acceleration), redirected by a bending magnet(s), or focused with magnetic or electrostatic lenses, and knowledge of the beam space charge is needed for optimal design of the optical elements. In ion implantation application, any build-up of positive charge in the insulating targets must be compensated by a simultaneous flux of cold electrons so as to provide overall charge neutrality of the target. We show that in line-of-sight ion implantation using a vacuum arc ion source, the high current ion beam carries along its own background sea of cold electrons, and this copious source of electrons provides a ''self-neutralizing'' feature to the beam. Here we describe experiments carried out in order to demonstrate this effect, and we provide an analysis showing that the beam is space-charge-neutralized to a very high degree.

  20. Neutralizing antibodies against interferon-Beta.

    PubMed

    Sorensen, Per Soelberg

    2008-09-01

    The development of neutralizing antibodies (NAbs) is a major problem in multiple sclerosis (MS) patients treated with interferon-beta (IFN-ß). Whereas binding antibodies (BAbs) can be demonstrated in the vast majority of patients, only a smaller proportion of patients develop NAbs. The principle in NAb in vitro assays is the utilization of cultured cell lines that are responsive to IFN-ß. The cytopathic effect (CPE) assay measures the capacity of NAbs to neutralize IFN- ß's protective effect on cells challenged with virus and the MxA induction assay measures the ability of NAbs to reduce the IFN-ß-induced expression of MxA, either at the mRNA or the protein level. A titer of >20 neutralizing units/ml traditionally defines NAb posi-tivity. NAbs in high titers completely abrogate the in vivo response to IFN-ß, whereas the effect of low and intermediate titers is unpredictable. As clinically important NAbs appear only after 9-18 months IFN- ß0 therapy, short-term studies of two years or less are unsuitable for evaluation of clinical NAb effects. All long-term trials of three years or more concordantly show evidence of a detrimental effect of NAbs on relapses, disease activity on MRI, or on disease progression. Persistent high titers of NAbs indicate an abrogation of the biological response and, hence, absence of therapeutic efficacy, and this observation should lead to a change of therapy. As low and medium titers are ambiguous treatment decisions in patients with low NAb titres should be guided by determination of in vivo mRNA MxA induction and clinical disease activity.

  1. A molecularly cloned, pathogenic, neutralization-resistant simian immunodeficiency virus, SIVsmE543-3.

    PubMed Central

    Hirsch, V; Adger-Johnson, D; Campbell, B; Goldstein, S; Brown, C; Elkins, W R; Montefiori, D C

    1997-01-01

    An infectious molecular clone of simian immunodeficiency virus SIVsm was derived from a biological isolate obtained late in disease from an immunodeficient rhesus macaque (E543) with SIV-induced encephalitis. The molecularly cloned virus, SIVsmE543-3, replicated well in macaque peripheral blood mononuclear cells and monocyte-derived macrophages and resisted neutralization by heterologous sera which broadly neutralized genetically diverse SIV variants in vitro. SIVsmE543-3 was infectious and induced AIDS when inoculated intravenously into pig-tailed macaques (Macaca nemestrina). Two of four infected macaques developed no measurable SIV-specific antibody and succumbed to a wasting syndrome and SIV-induced meningoencephalitis by 14 and 33 weeks postinfection. The other two macaques developed antibodies reactive in Western blot and virus neutralization assays. One macaque was sacrificed at 1 year postinoculation, and the survivor has evidence of immunodeficiency, characterized by persistently low CD4 lymphocyte subsets in the peripheral blood. Plasma samples from these latter animals neutralized SIVsmE543-3 but with much lower efficiency than neutralization of other related SIV strains, confirming the difficulty by which this molecularly cloned virus is neutralized in vitro. SIVsmE543-3 will provide a valuable reagent for studying SIV-induced encephalitis, mapping determinants of neutralization, and determining the in vivo significance of resistance to neutralization in vitro. PMID:8995688

  2. Vortex Formation in a Plasma Interacting with Neutral Flow

    SciTech Connect

    Tanaka, M. Y.; Ogiwara, K.; Etoh, S.; Aramaki, M.; Yoshimura, S.; Varanjes, J.

    2008-10-15

    Recently, it has been observed that there exists a class of vortices which rotates in the opposite direction to ExB drift (referred to as anti-ExB vortex). This result suggests that a predominant force other than electric field is acting on ions. It is found that momentum transport and resultant force generation through the interaction between ions and neutral flow play an essential role on anti-ExB vortex formation. The existence of inward neutral flow, which drives the ions in the anti-ExB direction, has been confirmed using a newly-developed high-resolution laser induced fluorescence (LIF) spectroscopy system.

  3. Measurement of plasma production and neutralization in gas neutralizers

    SciTech Connect

    Maor, D.; Meron, M.; Johnson, B.; Jones, K.; Agagu, A.; Hu, B.

    1986-06-17

    In order to satisfy the need of experimental data for the designing of gas neutralizers we have started a project aimed at measuring all relevant cross sections for the charge exchange of H/sup -/, H/sup 0/ and H/sup +/ projectiles, as well as the cross sections for the production of ions in the target. The expected results of these latter measurements are shown schematically.

  4. Charge neutralization as studied experimentally and theoretically

    NASA Technical Reports Server (NTRS)

    Linson, L. M.

    1982-01-01

    Problems regarding an isolated sphere which emits negative charge are considered. Such a sphere could charge up to large potentials which would inhibit the electron beam from leaving the vicinity of the body. In order to avoid charging to high potentials, a vehicle must attract a return current equal to the emitted current. The present investigation is concerned with theoretical models of some processes believed to be important for the vehicle neutralization problem under various conditions. Attention is given to general time-scale considerations, the low-altitude regime, the high-altitude regime, vehicle-induced discharge, and beam-plasma discharge. The general pattern which emeres as a result of measurements is that below altitudes of approximately 125 + or - 5 km the vehicle potential rarely rises more than several tens of volts.

  5. Advanced satellite sensors: Low Energy Neutral Atom (LENA) imager

    SciTech Connect

    Funsten, H.O.; McComas, D.J.

    1996-09-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Imaging of low energy neutral atoms (LENDs) created by electron capture by magnetospheric plasma ions from interactions with cold geocoronal neutrals promises to be a revolutionary technique for providing unprecedented information about the global structure and dynamics of the terrestrial magnetosphere. This has significant implications in space weather forecasting, weather-induced satellite upset diagnostics, and revolutionary insights into global magnetospheric physics. The Los Alamos Space and Atmospheric Sciences Group has completed extensive neutral atom simulations and detailed instrument definition, and we designed a proof-of-concept demonstration prototype and have obtained externally- funded programs for full instrument development

  6. Flavor changing neutral currents in a realistic composite technicolor model

    NASA Astrophysics Data System (ADS)

    Carone, Christopher D.; Hamilton, Rowan T.

    1993-03-01

    We consider the phenomenology of a composite technicolor model proposed recently by Georgi. Composite technicolor interactions produce four-quark operators in the low energy theory that contribute to flavor changing neutral current processes. While we expect operators of this type to be induced at the compositeness scale by the flavor-symmetry breaking effects of the preon mass matrices, the Georgi model also includes operators from higher scales that are not GIM-suppressed. Since these operators are potentially large, we study their impact on flavor changing neutral currents and CP violation in the neutral K, B, and D meson systems. Notably, we find that this model gives rise to a typical value for {ɛ‧}/{ɛ} that is much smaller than most standard model estimates.

  7. Immunogenic peptides comprising a T-helper epitope and a B-cell neutralizing antibody epitope

    DOEpatents

    Haynes, Barton F.; Korber, Bette T.; De Lorimier, Robert M.

    2006-12-26

    The present invention relates, generally, to a polyvalent immunogen and, more particularly, to a method of inducing neutralizing antibodies against HIV and to a polyvalent immunogen suitable for use in such a method.

  8. Optimization and revision of the production process of the Necator americanus glutathione S-transferase 1 (Na-GST-1), the lead hookworm vaccine recombinant protein candidate.

    PubMed

    Curti, Elena; Seid, Christopher A; Hudspeth, Elissa; Center, Lori; Rezende, Wanderson; Pollet, Jeroen; Kwityn, Cliff; Hammond, Molly; Matsunami, Rise K; Engler, David A; Hotez, Peter J; Elena Bottazzi, Maria

    2014-01-01

    Infection by the human hookworm Necator americanus is a leading cause of anemia and disability in the developing countries of Africa, Asia, and the Americas. In order to prevent childhood hookworm disease in resource poor settings, a recombinant vaccine is under development by the Sabin Vaccine Institute and Texas Children's Hospital Center for Vaccine Development, a Product Development Partnership (PDP). Previously, we reported on the expression and purification of a highly promising hookworm vaccine candidate, Na-GST-1, an N. americanus glutathione s-transferase expressed in Pichia pastoris (yeast), which led to production of 1.5 g of 95% pure recombinant protein at a 20L scale. (1) (,) (2) (,) (3) This yield and purity of Na-GST-1 was sufficient for early pilot manufacturing and initial phase 1 clinical testing. However, based on the number of doses which would be required to allow mass vaccination and a potential goal to deliver a vaccine as inexpensively as possible, a higher yield of expression of the recombinant antigen at the lowest possible cost is highly desirable. Here we report on modifications to the fermentation (upstream process) of the antigen expressed in P. pastoris, and to the purification (downstream process) of the recombinant protein that allowed for a 2-3-fold improvement in the final yield of Na-GST-1 purified protein. The major improvements included upstream process changes such as the addition of a sorbitol pulse and co-feed during methanol induction as well as an extension of the induction stage to approximately 96 hours; downstream process changes included modifying the UFDF to flat sheet with a 10 kDa Molecular Weight cut-off (MWCO), adjusting the capacity of an ion-exchange chromatography step utilizing a gradient elution as opposed to the original step elution, and altering the hydrophobic interaction chromatography conditions. The full process, as well as the purity and stability profiles of the target Na-GST-1, and its formulation

  9. A comparison of human chorionic gonadotropin and luteinizing hormone releasing hormone on the induction of spermiation and amplexus in the American toad (Anaxyrus americanus)

    PubMed Central

    2012-01-01

    Background Captive breeding programs for endangered amphibian species often utilize exogenous hormones for species that are difficult to breed. The purpose of our study was to compare the efficacy of two different hormones at various concentrations on sperm production, quantity and quality over time in order to optimize assisted breeding. Methods Male American toads (Anaxyrus americanus) were divided into three separate treatment groups, with animals in each group rotated through different concentrations of luteinizing hormone releasing hormone analog (LHRH; 0.1, 1.0, 4.0 and 32 micrograms/toad), human chorionic gonadotropin (hCG; 50, 100, 200, and 300 IU), or the control over 24 hours. We evaluated the number of males that respond by producing spermic urine, the sperm concentration, percent motility, and quality of forward progression. We also evaluated the effects of hCG and LHRH on reproductive behavior as assessed by amplexus. Data were analyzed using the Generalized Estimating Equations incorporating repeated measures over time and including the main effects of treatment and time, and the treatment by time interaction. Results The hormone hCG was significantly more effective at stimulating spermiation in male Anaxyrus americanus than LHRH and showed a dose-dependent response in the number of animals producing sperm. At the most effective hCG dose (300 IU), 100% of the male toads produced sperm, compared to only 35% for the best LHRH dose tested (4.0 micrograms). In addition to having a greater number of responders (P < 0.05), the 300 IU hCG treatment group had a much higher average sperm concentration (P < 0.05) than the treatment group receiving 4.0 micrograms LHRH. In contrast, these two treatments did not result in significant differences in sperm motility or quality of forward progressive motility. However, more males went into amplexus when treated with LHRH vs. hCG (90% vs. 75%) by nine hours post-administration. Conclusion There is a clear

  10. Rocket Experiment For Neutral Upwelling

    NASA Astrophysics Data System (ADS)

    Kenward, D. R.; Lessard, M.

    2015-12-01

    Observations from the CHAMP satellite from 2004 show relatively small scale heating in the thermosphere. Several different mechanisms have been proposed to explain this phenomenon. The RENU 2 rocket mission includes a suite of 14 instruments which will acquire data to help understand processes involved in neutral upwelling in the cusp. Neutral, ion, and electron measurements will be made to provide an assessment of the upwelling process. SUPERDarn measurements of large- scale Joule heating in the cusp during overflight will also be acquired. Small-scale data which could possibly be associated with Alfvén waves, will be acquired using onboard electric field measurements. In-situ measurement of precipitating electrons and all other measurements will be used in thermodynamic and electrodynamic models for comparison to the observed upwelling.

  11. Sq Currents and Neutral Winds

    NASA Astrophysics Data System (ADS)

    Yamazaki, Y.

    2015-12-01

    The relationship between ionospheric dynamo currents and neutral winds is examined using the Thermosphere Ionosphere Mesosphere Electrodynamic General Circulation Model (TIME-GCM). The simulation is run for May and June 2009 with variable neutral winds but with constant solar and magnetospheric energy inputs, which ensures that day-to-day changes in the solar quiet (Sq) current system arise only from lower atmospheric forcing. The intensity and focus position of the simulated Sq current system exhibit large day-to-day variability, as is also seen in ground magnetometer data. We show how the day-to-day variation of the Sq current system relate to variable winds at various altitudes, latitudes, and longitudes.

  12. Optimization of Neutral Atom Imagers

    NASA Technical Reports Server (NTRS)

    Shappirio, M.; Coplan, M.; Balsamo, E.; Chornay, D.; Collier, M.; Hughes, P.; Keller, J.; Ogilvie, K.; Williams, E.

    2008-01-01

    The interactions between plasma structures and neutral atom populations in interplanetary space can be effectively studied with energetic neutral atom imagers. For neutral atoms with energies less than 1 keV, the most efficient detection method that preserves direction and energy information is conversion to negative ions on surfaces. We have examined a variety of surface materials and conversion geometries in order to identify the factors that determine conversion efficiency. For chemically and physically stable surfaces smoothness is of primary importance while properties such as work function have no obvious correlation to conversion efficiency. For the noble metals, tungsten, silicon, and graphite with comparable smoothness, conversion efficiency varies by a factor of two to three. We have also examined the way in which surface conversion efficiency varies with the angle of incidence of the neutral atom and have found that the highest efficiencies are obtained at angles of incidence greater then 80deg. The conversion efficiency of silicon, tungsten and graphite were examined most closely and the energy dependent variation of conversion efficiency measured over a range of incident angles. We have also developed methods for micromachining silicon in order to reduce the volume to surface area over that of a single flat surface and have been able to reduce volume to surface area ratios by up to a factor of 60. With smooth micro-machined surfaces of the optimum geometry, conversion efficiencies can be increased by an order of magnitude over instruments like LENA on the IMAGE spacecraft without increase the instruments mass or volume.

  13. Plasma sources for spacecraft neutralization

    NASA Technical Reports Server (NTRS)

    Davis, V. A.; Katz, I.; Mandell, M. J.

    1990-01-01

    The principles of the operation of plasma sources for the neutralization of the surface of a spacecraft traveling in the presence of hot plasma are discussed with special attention given to the hollow-cathode-based plasma contactors. Techiques are developed that allow the calculation of the potentials and particle densities in the near environment of a hollow cathode plasma contactor in both the test tank and the LEO environment. The techniques and codes were validated by comparison of calculated and measured results.

  14. A novel linear neutralizing epitope of hepatitis E virus.

    PubMed

    Tang, Zi-Min; Tang, Ming; Zhao, Min; Wen, Gui-Ping; Yang, Fan; Cai, Wei; Wang, Si-Ling; Zheng, Zi-Zheng; Xia, Ning-Shao

    2015-07-01

    Hepatitis E virus (HEV) is a serious public health problem that causes acute hepatitis in humans and is primarily transmitted through fecal and oral routes. The major anti-HEV antibody responses are against conformational epitopes located in a.a. 459-606 of HEV pORF2. All reported neutralization epitopes are present on the dimer domain constructed by this peptide. While looking for a neutralizing monoclonal antibody (MAb)-recognized linear epitope, we found a novel neutralizing linear epitope (L2) located in a.a. 423-437 of pORF2. Moreover, epitope L2 is proved non-immunodominant in the HEV-infection process. Using the hepatitis B virus core protein (HBc) as a carrier to display this novel linear epitope, we show herein that this epitope could induce a neutralizing antibody response against HEV in mice and could protect rhesus monkeys from HEV infection. Collectively, our results showed a novel non-immunodominant linear neutralizing epitope of hepatitis E virus, which provided additional insight of HEV vaccine. PMID:26051517

  15. Neutral-current x-distributions

    DOE R&D Accomplishments Database

    Friedman, J. I.; Kendall, H. W.; Bogert, D.; Burnstein, R.; Fisk, R.; Fuess, S.; Bofill, J.; Busza, W.; Eldridge, T.; Abolins, M.; Brock, R.; et al.

    1984-06-01

    The role of the semi leptonic neutral current interaction as a probe of nucleon structure is examined. Previous measurements of neutral current x-distributions are reviewed, and new results from the Fermilab - MIT - MSU collaboration are presented.

  16. Effects of phosphate neutralization on the shape of the AP-1 transcription factor binding site in duplex DNA.

    PubMed Central

    Tomky, L A; Strauss-Soukup, J K; Maher, L J

    1998-01-01

    Previous electrophoretic experiments suggest that the AP-1 site in duplex DNA bends in response to the pattern of amino acid charges distal to the basic region in bound bZIP proteins. The extent and direction of apparent DNA bending are consistent with the prediction that DNA will collapse locally upon asymmetric phosphate charge neutralization. To prove that asymmetric phosphate neutralization could produce the observed degree of DNA bending, the present experiments partially substitute anionic phosphate diesters in the AP-1 site with various numbers of neutral methylphosphonate linkages. DNA bending is induced toward the neutralized face of DNA. The degree of DNA bending induced by methylphosphonate substitution (approximately 3.5 degrees per neutralized phosphate) is comparable to that induced by GCN4 variants carrying increasing numbers of additional basic amino acids. It is plausible, therefore, that asymmetric phosphate neutralization is the cause of DNA bending in such complexes. PMID:9580678

  17. Plasma/Neutral-Beam Etching Apparatus

    NASA Technical Reports Server (NTRS)

    Langer, William; Cohen, Samuel; Cuthbertson, John; Manos, Dennis; Motley, Robert

    1989-01-01

    Energies of neutral particles controllable. Apparatus developed to produce intense beams of reactant atoms for simulating low-Earth-orbit oxygen erosion, for studying beam-gas collisions, and for etching semiconductor substrates. Neutral beam formed by neutralization and reflection of accelerated plasma on metal plate. Plasma ejected from coaxial plasma gun toward neutralizing plate, where turned into beam of atoms or molecules and aimed at substrate to be etched.

  18. Priming Effects for Affective vs. Neutral Faces

    ERIC Educational Resources Information Center

    Burton, Leslie A.; Rabin, Laura; Wyatt, Gwinne; Frohlich, Jonathan; Vardy, Susan B.; Dimitri, Diana

    2005-01-01

    Affective and Neutral Tasks (faces with negative or neutral content, with different lighting and orientation) requiring reaction time judgments of poser identity were administered to 32 participants. Speed and accuracy were better for the Affective than Neutral Task, consistent with literature suggesting facilitation of performance by affective…

  19. Neutral beamline with improved ion energy recovery

    DOEpatents

    Kim, Jinchoon

    1984-01-01

    A neutral beamline employing direct energy recovery of unneutralized residual ions is provided which enhances the energy recovery of the full energy ion component of the beam exiting the neutralizer cell, and thus improves the overall neutral beamline efficiency. The unneutralized full energy ions exiting the neutralizer are deflected from the beam path and the electrons in the cell are blocked by a magnetic field applied transverse to the beam direction in the neutral izer exit region. The ions which are generated at essentially ground potential and accelerated through the neutralizer cell by a negative acceleration voltage are collected at ground potential. A neutralizer cell exit end region is provided which allows the magnetic and electric fields acting on the exiting ions to be loosely coupled. As a result, the fractional energy ions exiting the cell are reflected onto and collected at an interior wall of the neutralizer formed by the modified end geometry, and thus do not detract from the energy recovery efficiency of full energy ions exiting the cell. Electrons within the neutralizer are prevented from exiting the neutralizer end opening by the action of crossed fields drift (ExB) and are terminated to a collector collar around the downstream opening of the neutralizer. The correct combination of the extended neutralizer end structure and the magnet region is designed so as to maximize the exit of full energy ions and to contain the fractional energy ions.

  20. Ion-beam Plasma Neutralization Interaction Images

    SciTech Connect

    Igor D. Kaganovich; Edward Startsev; S. Klasky; Ronald C. Davidson

    2002-04-09

    Neutralization of the ion beam charge and current is an important scientific issue for many practical applications. The process of ion beam charge and current neutralization is complex because the excitation of nonlinear plasma waves may occur. Computer simulation images of plasma neutralization of the ion beam pulse are presented.

  1. On abstract degenerate neutral differential equations

    NASA Astrophysics Data System (ADS)

    Hernández, Eduardo; O'Regan, Donal

    2016-10-01

    We introduce a new abstract model of functional differential equations, which we call abstract degenerate neutral differential equations, and we study the existence of strict solutions. The class of problems and the technical approach introduced in this paper allow us to generalize and extend recent results on abstract neutral differential equations. Some examples on nonlinear partial neutral differential equations are presented.

  2. The Net Neutrality Debate: The Basics

    ERIC Educational Resources Information Center

    Greenfield, Rich

    2006-01-01

    Rich Greenfield examines the basics of today's net neutrality debate that is likely to be an ongoing issue for society. Greenfield states the problems inherent in the definition of "net neutrality" used by Common Cause: "Network neutrality is the principle that Internet users should be able to access any web content they choose and use any…

  3. Comparison of experimental data and 3D simulations of ion beam neutralization from the neutralized transport experiment

    SciTech Connect

    Thoma, C.; Welch, D.R.; Yu, S.S.; Henestroza, E.; Roy, P.K.; Eylon, S.; Gilson, E.P.

    2004-09-22

    The Neutralized Transport Experiment (NTX) at Lawrence Berkeley National Laboratory has been designed to study the final focus and neutralization of high perveance ion beams for applications in heavy ion fusion (HIF) and high energy density physics (HEDP) experiments. Pre-formed plasmas in the last meter before the target of the scaled experiment provide a source of electrons which neutralize the ion current and prevent the space-charge induced spreading of the beam spot. NTX physics issues are discussed and experimental data is analyzed and compared with 3D particle-in-cell simulations. Along with detailed target images, 4D phase-space data of the NTX at the entrance of the neutralization region has been acquired. This data is used to provide a more accurate beam distribution with which to initialize the simulation. Previous treatments have used various idealized beam distributions which lack the detailed features of the experimental ion beam images. Simulation results are compared with NTX experimental measurements for 250 keV K{sup +} ion beams with dimensionless perveance of 1-7 x 10{sup -4}. In both simulation and experiment, the deduced beam charge neutralization is close to the predicted maximum value.

  4. Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus).

    PubMed

    Cipollini, Don; Rigsby, Chad M

    2015-10-01

    We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB. PMID:26314014

  5. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    PubMed

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears.

  6. Application of Large-Scale Parentage Analysis for Investigating Natal Dispersal in Highly Vagile Vertebrates: A Case Study of American Black Bears (Ursus americanus)

    PubMed Central

    Moore, Jennifer A.; Draheim, Hope M.; Etter, Dwayne; Winterstein, Scott; Scribner, Kim T.

    2014-01-01

    Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540) from three generations of black bears (Ursus americanus) harvested in a large (47,739 km2), geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337). We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed) but a small proportion (21%) of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km) were comparable to male dispersal distances (59.0±3.2 km). Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1) intensive harvest promotes restricted dispersal, or 2) high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species. PMID:24621593

  7. Molecular phylogeny and SNP variation of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) derived from genome sequences.

    PubMed

    Cronin, Matthew A; Rincon, Gonzalo; Meredith, Robert W; MacNeil, Michael D; Islas-Trejo, Alma; Cánovas, Angela; Medrano, Juan F

    2014-01-01

    We assessed the relationships of polar bears (Ursus maritimus), brown bears (U. arctos), and black bears (U. americanus) with high throughput genomic sequencing data with an average coverage of 25× for each species. A total of 1.4 billion 100-bp paired-end reads were assembled using the polar bear and annotated giant panda (Ailuropoda melanoleuca) genome sequences as references. We identified 13.8 million single nucleotide polymorphisms (SNP) in the 3 species aligned to the polar bear genome. These data indicate that polar bears and brown bears share more SNP with each other than either does with black bears. Concatenation and coalescence-based analysis of consensus sequences of approximately 1 million base pairs of ultraconserved elements in the nuclear genome resulted in a phylogeny with black bears as the sister group to brown and polar bears, and all brown bears are in a separate clade from polar bears. Genotypes for 162 SNP loci of 336 bears from Alaska and Montana showed that the species are genetically differentiated and there is geographic population structure of brown and black bears but not polar bears. PMID:24477675

  8. Time course of oocyte development in winter flounder Pseudopleuronectes americanus and spawning seasonality for the Gulf of Maine, Georges Bank and southern New England stocks.

    PubMed

    Press, Y K; McBride, R S; Wuenschel, M J

    2014-08-01

    Winter flounder Pseudopleuronectes americanus were collected at monthly intervals from December 2009 to May 2011, to describe the pattern and seasonality of oocyte development, including: (1) the group-synchronous transition from primary to secondary oocytes that initiates immediately after spawning, (2) the slow (months) development of vitellogenic oocytes followed by the rapid (weeks) maturation of oocytes, (3) the synchronous nature of mature oocytes ovulating, but the discrete releases of benthic eggs in batches, (4) the protracted (months) degradation of postovulatory follicles and (5) the occurrence of follicular atresia. Although fish were collected across only c. 2° latitudinal range, the spawning season was c. 1 month later in the Gulf of Maine (GOM) than on Georges Bank and in southern New England. This is probably due to lower temperatures in the GOM. These stock-specific data regarding the time course of oogenesis are of practical value. This information is discussed in relation to measuring and interpreting elements of reproductive potential such as maturation, skipped spawning and fecundity, the response of reproductive traits by this widely distributed species to changing climate and the response by this common, marine-estuarine species to urbanization, particularly environmental pollutants and dredging.

  9. Effects of molting and environmental factors on trace metal body-burdens and hemocyanin concentrations in the American lobster, Homarus americanus.

    PubMed

    Engel, D W; Brouwer, M; Mercaldo-Allen, R

    2001-09-01

    Hemocyanin concentrations in the hemolymph of marine crustacea are dependent on the molt cycle and on environmental conditions. Studies in our laboratories have found that hemocyanin levels in blue crabs are reduced after ecdysis and under conditions of environmental stress (Engel, Brouwer, & McKenna, 1993. Hemocyanin concentrations in marine crustaceans as a function of environmental conditions. Marine Ecology Progress Series, 93, 233-244). We have extended those studies to include the American lobster, Homarus americanus. Hemolymph and digestive gland tissues from Long Island Sound lobsters were analyzed for hemocyanin, copper, and zinc during different stages of the molt cycle. Hemocyanin, copper and zinc in the hemolymph were highest in premolt stages (D1-D4), and lowest in the postecdysal papershell stages (B1-B2). Concomitantly, copper in digestive glands decreased significantly following ecdysis, but no significant changes in the metals bound to metallothionein (MT) were observed. Copper-MT was the predominant form throughout the molt cycle, presumably because lobsters were obtained from copper-contaminated areas. To examine the effects of environmental factors, intermolt lobsters were collected from locations of different environmental quality along the Atlantic coast, and were analyzed for hemocyanin and trace metals. In general, animals from areas with a history of contamination showed the highest hemocyanin concentrations.

  10. Crystallization and preliminary X-ray analysis of Na-ASP-1, a multi-domain pathogenesis-related-1 protein from the human hookworm parasite Necator americanus

    PubMed Central

    Asojo, Oluwatoyin A.; Loukas, Alex; Inan, Mehmet; Barent, Rick; Huang, Jicai; Plantz, Brad; Swanson, Amber; Gouthro, Mark; Meagher, Michael M.; Hotez, Peter J.

    2005-01-01

    Human hookworm infection is a major cause of anemia and malnutrition in the developing world. In an effort to control hookworm infection, the Human Hookworm Vaccine Initiative has identified candidate vaccine antigens from the infective larval stage (L3) of the parasite, including a family of pathogenesis-related-1 (PR-1) proteins known as the ancylostoma-secreted proteins (ASPs). The functions of the ASPs are unknown. In addition, it is unclear why some ASPs have one while others have multiple PR-1 domains. There are no known structures of a multi-domain ASP and in an effort to remedy this situation, recombinant Na-ASP-1 has been expressed, purified and crystallized. Na-ASP-1 is a 406-amino-acid multi-domain ASP from the prevalent human hookworm parasite Necator americanus. Useful X-ray data to 2.2 Å have been collected from a crystal that belongs to the monoclinic space group P21 with unit-cell parameters a = 67.7, b = 74.27, c = 84.60 Å, β = 112.12°. An initial molecular-replacement solution has been obtained with one monomer in the asymmetric unit. PMID:16511050

  11. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus).

    PubMed

    Moore, Jennifer A; Draheim, Hope M; Etter, Dwayne; Winterstein, Scott; Scribner, Kim T

    2014-01-01

    Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540) from three generations of black bears (Ursus americanus) harvested in a large (47,739 km2), geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337). We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed) but a small proportion (21%) of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km) were comparable to male dispersal distances (59.0±3.2 km). Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1) intensive harvest promotes restricted dispersal, or 2) high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species. PMID:24621593

  12. Comparative reproductive success of winter flounder in Long Island Sound: A three-year study (biology, biochemistry, and chemistry). [Pseudopleuronectes americanus

    SciTech Connect

    Nelson, D.A.; Miller, J.E.; Rusanowsky, D.; Greig, R.A.; Sennefelder, G.R.; Mercaldo-Allen, R.; Kuropat, C.; Gould, E.; Thurberg, F.P.; Calabrese, A. )

    1991-09-01

    In a 3-yr study, late prespawning winter flounder (Pseudopleuronectes americanus) were collected from various stations in Long Island Sound (three of them heavily urbanized) and spawned in the laboratory. For comparative purposes, flounder from two sites in the Boston Harbor area were similarly treated in 1987 and 1988. Of the stations in Long Island Sound, New Haven Harbor alone consistently produced low percent viable hatch and small larvae. Boston Harbor produced the smallest larvae of all sites. There were no significant station-to-station differences in lipid utilization during larval development; yolk reserves at stations showing a low percent viable hatch, small larvae, and low embryonic development rate were probably used in part for stress metabolism. No significant differences in concentrations of polychlorinated biphenyls for collections from Long Island Sound were found either in livers of spawned fish, in sediments, or in eggs of winter flounder. The very low metal concentrations in winter flounder eggs showed no relation to the degree of metal contamination found at stations in Long Island Sound and Boston Harbor.

  13. Structure of glutathione S-transferase 1 from the major human hookworm parasite Necator americanus (Na-GST-1) in complex with glutathione.

    PubMed

    Asojo, Oluwatoyin A; Ceccarelli, Christopher

    2014-09-01

    Glutathione S-transferase 1 from Necator americanus (Na-GST-1) is a vaccine candidate for hookworm infection that has a high affinity for heme and metal porphyrins. As part of attempts to clarify the mechanism of heme detoxification by hookworm GSTs, co-crystallization and soaking studies of Na-GST-1 with the heme-like molecules protoporphyrin IX disodium salt, hematin and zinc protoporphyrin were undertaken. While these studies did not yield the structure of the complex of Na-GST-1 with any of these molecules, co-crystallization experiments resulted in the first structures of the complex of Na-GST-1 with the substrate glutathione. The structures of the complex of Na-GST-1 with glutathione were solved from pathological crystalline aggregates comprising more than one crystal form. These first structures of the complex of Na-GST-1 with the substrate glutathione were solved by molecular replacement from data collected with a sealed-tube home source using the previously reported apo structure as the search model.

  14. Black bear (Ursus americanus Pallas) feeding damage across timber harvest edges in northern California coast redwood (Sequoia sempervirens[D. Don] Endl.) forests, USA

    USGS Publications Warehouse

    Russell, W.H.; Carnell, K.; McBride, J.R.

    2001-01-01

    Feeding damage to trees by black bears (Ursus americanus Pallas) was recorded in proximity to timber harvest edges in harvested and old-growth stands of coast redwood (Sequoia sempervirens [D. Don] Endl.) in northern California, USA. Bears exhibited distinct preference in their feeding patterns related to stand structure and composition and to distance from the timber-harvest edge. Most damage was recorded within regenerating stands. Regression analysis indicated that density of damaged trees was negatively correlated with distance from timber harvest edges within old-growth stands. A significant negative correlation was also found between the density of trees damaged by bears and habitat diversity (H') as measured by the Shannon diversity index. In addition, bears exhibited preference for pole-size trees (dbh = 10-50 cm) over all other size classes, and coast redwood over other species. In general, damage by bears appeared to act as a natural thinning agent in even-aged stands. No damage was recorded in old-growth stands except in close proximity to the timber-harvest edge where subcanopy recruitment was high.

  15. Incidence of Infestation and Larval Success of Emerald Ash Borer (Agrilus planipennis) on White Fringetree (Chionanthus virginicus), Chinese Fringetree (Chionanthus retusus), and Devilwood (Osmanthus americanus).

    PubMed

    Cipollini, Don; Rigsby, Chad M

    2015-10-01

    We compared the incidence of infestation by emerald ash borer (EAB) and lilac borer on white fringetree to that of its Asian congener, Chinese fringetree, Chionanthus retusus, and a North American relative, devilwood, Osmanthus americanus. We also conducted laboratory bioassays to determine the suitability of these hosts for EAB larvae. At Spring Grove Cemetery and Arboretum in Cincinnati, Ohio, 9 of 28 white fringetrees examined were infested by EAB. Most of the white fringetrees had lilac borer infestation, and most of the trees infested by EAB also had lilac borer infestation. None of the 11 Chinese fringetrees examined were infested by either EAB or lilac borer. Each of the five devilwood individuals examined was infested by lilac borer, but not EAB. At The Morton Arboretum in Lisle, Illinois, 7 of 16 white fringetrees examined were infested by EAB, while none of the seven Chinese fringetrees examined were infested by either insect. A 40-d bioassay confirmed that white fringetree was an acceptable host, producing fourth-instar larvae that were smaller than those produced on a highly susceptible cultivar of green ash, Fraxinus pennsylvanica. No larvae survived on Chinese fringetree, and neonates were largely incapable of feeding on it. Two larvae survived on devilwood, reaching the second instar and excavating extensive galleries. Future work should be aimed at biotic and abiotic factors influencing the susceptibility of white fringetree, as well as further examination of close relatives for their vulnerability to EAB.

  16. Epidemiology of Necator americanus hookworm infections in Xiulongkan Village, Hainan Province, China: high prevalence and intensity among middle-aged and elderly residents.

    PubMed

    Gandhi, N S; Jizhang, C; Khoshnood, K; Fuying, X; Shanwen, L; Yaoruo, L; Bin, Z; Haechou, X; Chongjin, T; Yan, W; Wensen, W; Dungxing, H; Chong, C; Shuhua, X; Hawdon, J M; Hotez, P J

    2001-08-01

    Hookworm is highly endemic to Hainan Province, an island located in the South China Sea. To investigate the prevalence and intensity of infection in the area, the village of Xiulongkan was surveyed between April and July 1998. A cross-sectional study was conducted in which fecal samples of 80% of the village residents (631 individuals) were tested for the presence of helminth eggs. Hookworm was the predominant intestinal helminth in Xiulongkan, where it was determined that 60% of those tested were infected. Necator americanus was the predominant species of hookworm in this population. The prevalence of hookworm increased with age, and then leveled to a plateau for ages 41 yr and up. This observation was in contrast to infections with Ascaris lumbricoides, where the highest prevalences occurred among school-aged children. Women had a significantly higher prevalence of hookworm than men and this difference emerged in early adulthood. The intensity of hookworm infection also significantly increased with age, with the highest intensity infections occurring among middle-aged and elderly residents. Females were more likely to have moderate or heavy infections, whereas males were more likely to have light infections. The rates of hookworm transmission are particularly high among the middle-aged and elderly residents of Xiulongkan.

  17. Nonlinear neutral inclusions: assemblages of coated ellipsoids

    PubMed Central

    Bolaños, Silvia Jiménez; Vernescu, Bogdan

    2015-01-01

    The problem of determining nonlinear neutral inclusions in (electrical or thermal) conductivity is considered. Neutral inclusions, inserted in a matrix containing a uniform applied electric field, do not disturb the field outside the inclusions. The well-known Hashin-coated sphere construction is an example of a neutral inclusion. In this paper, we consider the problem of constructing neutral inclusions from nonlinear materials. In particular, we discuss assemblages of coated ellipsoids. The proposed construction is neutral for a given applied field. PMID:26064633

  18. Kinetic Simulations of Ion Beam Neutralization

    SciTech Connect

    Wang, Joseph

    2010-05-21

    Ion beam emission/neutralization is one of the most fundamental problems in spacecraft plasma interactions and electric propulsion. Although ion beam neutralization is readily achieved in experiments, the understanding of the underlying physical process remains at a rather primitive level. No theoretical or simulation models have convincingly explained the detailed neutralization mechanism, and no conclusions have been reached. This paper presents a fully kinetic simulation of ion beam neutralization and plasma beam propagation and discusses the physics of electron-ion coupling and the resulting propagation of a neutralized mesothermal plasma.

  19. Neutral gas dynamics in fireballs

    SciTech Connect

    Stenzel, R. L.; Ionita, C.; Schrittwieser, R.

    2011-06-01

    Fireballs are local discharge phenomena on positively biased electrodes in partially ionized plasmas. Electrons, energized at a double layer, heat neutral gas which expands. The gas pressure exceeds the plasma pressure, hence becomes important to the stability and transport in fireballs. The flow of gas moves the electrode and sensors similar to a mica pendulum. Flow speed and directions are measured. A fireball gun has been developed to partially collimate the flow of hot gas and heat objects in its path. New applications of fireballs are suggested.

  20. Advanced neutral-beam technology

    SciTech Connect

    Berkner, K.H.

    1980-09-01

    Extensive development will be required to achieve the 50- to 75-MW, 175- to 200-keV, 5- to 10-sec pulses of deuterium atoms envisioned for ETF and INTOR. Multi-megawatt injector systems are large (and expansive); they consist of large vacuum tanks with many square meters of cryogenic pumping panels, beam dumps capable of dissipating several megawatts of un-neutralized beam, bending magnets, electrical power systems capable of fast turnoff with low (capacity) stored energy, and, of course, the injector modules (ion sources and accelerators). The technology requirements associated with these components are described.

  1. Chord integrated neutral particle diagnostic data analysis for neutral beam injection and ion cyclotron radio frequency heated plasma in a complex Large Helical Device geometry

    SciTech Connect

    Veshchev, E. A.; Goncharov, P. R.; Ozaki, T.; Sudo, S.; Lyon, J. F.

    2006-10-15

    Energy and angle-resolved measurements of charge exchange neutral particle fluxes from the plasma provide information about T{sub i}, as well as non-Maxwellian substantially anisotropic ion distribution tails due to neutral beam injection (NBI) and ion cyclotron radio frequency (ICRF) heating. The measured chord integral neutral flux calculation scheme for the Large Helical Device magnetic surface geometry is given. Calculation results are shown for measurable atomic energy spectra corresponding to heating-induced fast ion distributions from simplified Fokker-Planck models. The behavior of calculated and experimental suprathermal particle distributions from NBI and ICRF heated plasma is discussed in the context of the experimental data interpretation.

  2. Creating and studying ion acoustic waves in ultracold neutral plasmas

    SciTech Connect

    Killian, T. C.; Castro, J.; McQuillen, P.; O'Neil, T. M.

    2012-05-15

    We excite ion acoustic waves in ultracold neutral plasmas by imprinting density modulations during plasma creation. Laser-induced fluorescence is used to observe the density and velocity perturbations created by the waves. The effect of expansion of the plasma on the evolution of the wave amplitude is described by treating the wave action as an adiabatic invariant. After accounting for this effect, we determine that the waves are weakly damped, but the damping is significantly faster than expected for Landau damping.

  3. Boosting Heterosubtypic Neutralization Antibodies in Recipients of 2009 Pandemic H1N1 Influenza Vaccine

    PubMed Central

    Qiu, Chao; Huang, Yang; Wang, Qian; Tian, Di; Zhang, Wanju; Hu, Yunwen; Yuan, Zhenghong; Zhang, Xiaoyan

    2012-01-01

    Background. A mass vaccination has been implemented to prevent the spread of 2009 pandemic influenza virus in China. Highly limited information is available on whether this vaccine induces cross-reactive neutralization antibodies against other subtypes of influenza viruses. Methods. We employed pseudovirus-based assays to analyze heterosubtypic neutralization responses in serum samples of 23 recipients of 2009 pandemic influenza vaccine. Results. One dose of pandemic vaccine not only stimulated good neutralization antibodies against cognate influenza virus 2009 influenza A (H1N1), but also raised broad cross-reactive neutralization activities against seasonal H3N2 and highly pathogenic avian influenza virus H5N1 and lesser to H2N2. The cross-reactive neutralization activities were completely abolished after the removal of immunoglobin G (IgG). In contrast, H1N1 vaccination alone in influenza-naive mice elicited only vigorous homologous neutralizing activities but not cross-reactive neutralization activities. Conclusions. Our data suggest that the cross-reactive neutralization epitopes do exist in this vaccine and could elicit significant cross-reactive neutralizing IgG antibodies in the presence of preexisting responses. The exposure to H1N1 vaccine is likely to modify the hierarchical order of preexisting immune responses to influenza viruses. These findings provide insights into the evolution of human immunity to influenza viruses after experiencing multiple influenza virus infections and vaccinations. PMID:22052887

  4. Endotoxin neutralization with rabbit antisera to Escherichia coli J5 and other gram-negative bacteria.

    PubMed Central

    Warren, H S; Novitsky, T J; Bucklin, A; Kania, S A; Siber, G R

    1987-01-01

    To study the mechanisms of protection against endotoxin challenge offered by antisera to smooth and rough gram-negative organisms, we have developed an assay to quantitate endotoxin neutralization based on inhibition of the Limulus amoebocyte lysate test. Dilutions of different bacterial lipopolysaccharides (LPSs) were incubated with hyperimmune rabbit sera against Escherichia coli O113, E. coli O18, and rough mutants E. coli J5 and Salmonella minnesota Re595 and were then combined with limulus lysate. The gelation reaction induced by LPS in the lysate was monitored spectrophotometrically, and the concentration of LPS resulting in a 50% lysate response was determined and correlated with antibody titers measured by enzyme-linked immunosorbent assay. Antisera to smooth organisms neutralized homologous LPS markedly and heterologous LPSs only minimally relative to neutralization by preimmune serum. Neutralization of homologous LPS occurred immediately without preincubation of serum and LPS. Antisera to rough mutants neutralized more heterologous LPS than did antisera to smooth organisms. However, this heterologous neutralization required preincubation of serum and LPS and did not appear to be correlated with antibody concentrations. We conclude that antisera to LPS rapidly neutralize the biological activity of the homologous LPS, as detected by limulus lysate, and that neutralization is at least in part antibody mediated. Antisera to rough-mutant organisms slowly neutralized the activity of heterologous LPSs, but this effect appeared not to be correlated with concentrations of antibody to the LPS of the rough mutant, as measured by enzyme-linked immunosorbent assay. PMID:3298063

  5. Detailed Atomic Structure of Neutral and Near-Neutral Systems

    SciTech Connect

    Oliver, Paul; Hibbert, Alan

    2011-05-11

    This paper highlights the issues which need to be addressed in undertaking accurate calculations of multi-electron atoms and ions, particularly at or near the neutral end of an isoelectronic sequence. We illustrate the processes through two calculations--of transitions in Cl I and Sn II--and discuss the convergence of our results as well as updating previous work. In particular, in the case of Cl I, we propose new identifications of the levels involved in certain transitions which are important in determining the abundance of chlorine in the inter-stellar medium (ISM), while in singly ionised tin, our calculations suggest a re-evaluation of the the abundance of tin in the ISM. We also confirm recent identification of Sn II lines seen in tokamak plasmas.

  6. Ergonomically neutral arm support system

    DOEpatents

    Siminovitch, Michael J; Chung, Jeffrey Y; Dellinges, Steven; Lafever, Robin E

    2005-08-02

    An ergonomic arm support system maintains a neutral position for the forearm. A mechanical support structure attached to a chair or other mounting structure supports the arms of a sitting or standing person. The system includes moving elements and tensioning elements to provide a dynamic balancing force against the forearms. The support structure is not fixed or locked in a rigid position, but is an active dynamic system that is maintained in equipoise by the continuous operation of the opposing forces. The support structure includes an armrest connected to a flexible linkage or articulated or pivoting assembly, which includes a tensioning element such as a spring. The pivoting assembly moves up and down, with the tensioning element providing the upward force that balances the downward force of the arm.

  7. Neutral Hydrogen in Arp 158

    NASA Astrophysics Data System (ADS)

    Iyer, Mansie G.; Simpson, Caroline E.; Gottesman, Stephen T.; Malphrus, Benjamin K.

    2004-09-01

    We present 21 cm observations of Arp 158. We have performed a study of the neutral hydrogen (H I) to help us understand the overall formation and evolution of this system. This is a disturbed system with distinct optical knots connected by a linear structure embedded in luminous material. There is also a diffuse spray to the southeast. The H I seems to be made up of three distinct, kinematically separate systems. Arp 158 bears a certain optical resemblance to NGC 520 (Arp 157), which has been identified as a mid-stage merger. From our 21 cm observations of Arp 158, we also see a comparable H I content with NGC 520. These similarities suggest that Arp 158 is also an intermediate-stage merger.

  8. After treatment ends: neutral time.

    PubMed

    Hurt, G J; McQuellon, R P; Barrett, R J

    1994-01-01

    For persons diagnosed with cancer, the remission period may be marked by increased anxiety and distress. While the medical team may view remission as an eagerly anticipated milestone, the decreased medical surveillance during this time can cause a heightened fear of recurrence for the patient. One author has called this period of remission "neutral time," a time characterized by uncertainty. The safety signal hypothesis, developed by Martin Seligman, may help to explain the anxiety experienced by some patients during the remission period. Because cancer is frequently a silent disease with no overt symptoms, patients in remission often have no safety signal to indicate that the disease will not return. A case study is presented and discussed in light of these two concepts.

  9. An accessible heavy neutral lepton

    NASA Astrophysics Data System (ADS)

    Chang, Chao-Hsi

    1982-09-01

    In the SUL(2) ⊗ SUR(2) ⊗ UB-L(1) model, an accessible heavy neutral lepton may exist owing to the mixing of generations. Based on a rough estimate, it is pointed out that the most hopeful experiments to observe this lepton are ν-production in an emulsion (because the track of a particle with lifetime 10-11-10-13 s could be seen) and e-production. The author thanks Professor J.D. Bjorken, Professor He Zuo-Xiu, Professor R.E. Mashark, Professor S.J. Chang, Professor Zhu Cong-Yuan and Professor M. Dine for helpful discussions and comments. He would like to thank the referee for valuable comments.

  10. High Resolution Neutral Atom Microscope

    NASA Astrophysics Data System (ADS)

    Bucay, Igal; Castillo-Garza, Rodrigo; Stratis, Georgios; Raizen, Mark

    2015-03-01

    We are developing a high resolution neutral atom microscope based on metastable atom electron spectroscopy (MAES). When a metastable atom of a noble gas is near a solid, a surface electron will tunnel to an empty energy level of the metastable atom, thereby ejecting the excited electron from the atom. The emitted electrons carry information regarding the local topography and electronic, magnetic, and chemical structures of most hard materials. Furthermore, using a chromatic aberration corrected magnetic hexapole lens we expect to attain a spatial resolution below 10 nm. We will use this microscope to investigate how local phenomena can give rise to macroscopic effects in materials that cannot be probed using a scanning tunneling microscope, namely insulating transition metal oxides.

  11. Phenomenology of neutral heavy leptons

    SciTech Connect

    Kalyniak, P.; Melo, I.

    1997-02-01

    We continue our previous work on the flavor-conserving leptonic decays of the Z boson with neutral heavy leptons (NHL`s) in the loops by considering box, vertex, and self-energy diagrams for the muon decay. By inclusion of these loops (they contribute to the input parameter M{sub W}), we can probe the full parameter space spanned by the so-called flavor-conserving mixing parameters ee{sub mix},{mu}{mu}{sub mix},{tau}{tau}{sub mix}. We show that only two diagrams from each class (box, vertex, and self-energy) are important; further, after renormalization only two box diagrams {open_quotes}survive{close_quotes} as dominant. We compare the results of our analysis with the existing work in this field and conclude that flavor-conserving decays have certain advantages over traditionally considered flavor-violating ones. {copyright} {ital 1997} {ital The American Physical Society}

  12. Phenomenology of neutral heavy leptons

    NASA Astrophysics Data System (ADS)

    Kalyniak, Pat; Melo, I.

    1997-02-01

    We continue our previous work on the flavor-conserving leptonic decays of the Z boson with neutral heavy leptons (NHL's) in the loops by considering box, vertex, and self-energy diagrams for the muon decay. By inclusion of these loops (they contribute to the input parameter MW), we can probe the full parameter space spanned by the so-called flavor-conserving mixing parameters eemix,μμmix,ττmix. We show that only two diagrams from each class (box, vertex, and self-energy) are important; further, after renormalization only two box diagrams ``survive'' as dominant. We compare the results of our analysis with the existing work in this field and conclude that flavor-conserving decays have certain advantages over traditionally considered flavor-violating ones.

  13. Measurement of Neutral Hydrogen Density in a Helicon Plasma

    NASA Astrophysics Data System (ADS)

    Galante, M. E.; Magee, R. M.; McCarren, D. W.; Scime, E. E.; Brooks, N. H.; Boivin, R. L.

    2011-10-01

    A new diagnostic system based on two-photon absorption laser-induced fluorescence (TALIF) has been developed to measure neutral hydrogen density in the edge of fusion plasmas. 205 nm photons from a frequency tripled dye laser are injected co-propagating into the plasma chamber where they excite the 1s-3D transition in neutral hydrogen. The 3D state then decays emitting light at 656 nm. The emission intensity is directly proportional to the ground state hydrogen density. With the tabulated atomic absorption rates for hydrogen and krypton, TALIF measurements of krypton gas provide an absolute calibration. Here we present the technical details and measured performance of the TALIF system (laser line width, pulse length, pulse energy, RMS stability) and TALIF measurements of room temperature krypton gas. The krypton measurements are compared to expectations and the measured line widths are analyzed in terms of Doppler and saturation broadening. We also present TALIF measurements of the radial profiles of the absolute neutral hydrogen and neutral temperature in a helicon plasma source as a function of source parameters. Work supported in part by US DOE under DE-FC02-04ER54698.

  14. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus)

    PubMed Central

    Wong, Mabel T.; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A.; Master, Emma R.

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36–0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25–50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

  15. Discovery and description of a new trichostrongyloid species (Nematoda: Ostertagiinae), abomasal parasites in mountain goat, Oreamnos americanus, from the Western Cordillera of North America.

    PubMed

    Hoberg, Eric P; Abrams, Arthur; Pilitt, Patricia A; Jenkins, Emily J

    2012-08-01

    Marshallagia lichtenfelsi sp. n. is a dimorphic ostertagiine nematode occurring in the abomasum of mountain goats, Oreamnos americanus, from the Western Cordillera of North America. Major and minor morphotype males and females are characterized and distinguished relative to the morphologically similar Marshallagia marshalli / Marshallagia occidentalis from North America and Marshallagia dentispicularis, along with other congeners, from the Palearctic region. The configuration of the convoluted and irregular synlophe in the cervical region of males and females of M. lichtenfelsi is apparently unique, contrasting with a continuous and parallel system of ridges among those species of Marshallagia, including M. marshalli/M. occidentalis, which have been evaluated. Specimens of M. lichtenfelsi are further defined by the rectangular form of the accessory bursal membrane (width > length) in the major morphotype and by the trapezoidal Sjöberg's organ in the minor morphotype, in addition to specific attributes of the spicules and spicule tips. We regard 12 species, including the proposed new taxon, to be valid. Primary diagnostic characters are reviewed for Marshallagia and a framework is presented for standardization of future descriptions incorporating the synlophe in males and females and the structure of the spicules and genital cone in major and minor morphotype males. The center of diversity for species of Marshallagia is the mountain-steppe region of central Eurasia where 11 species (including the Holarctic M. marshalli) are recognized in association with Caprini, Rupicaprini, and Antelopinae; only 2 species occur in the Nearctic. In this assemblage, M. lichtenfelsi is endemic to North America and limited in host distribution to mountain goats. An intricate history for refugial isolation and population fragmentation demonstrated for mountain goats and wild sheep indicates the potential for considerable cryptic diversity for Marshallagia and other nematodes. Shifting

  16. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

    PubMed

    Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities. PMID:27446004

  17. Role of Ih in differentiating the dynamics of the gastric and pyloric neurons in the stomatogastric ganglion of the lobster, Homarus americanus.

    PubMed

    Zhu, Lin; Selverston, Allen I; Ayers, Joseph

    2016-06-01

    The hyperpolarization-activated inward cationic current (Ih) is known to regulate the rhythmicity, excitability, and synaptic transmission in heart cells and many types of neurons across a variety of species, including some pyloric and gastric mill neurons in the stomatogastric ganglion (STG) in Cancer borealis and Panulirus interruptus However, little is known about the role of Ih in regulating the gastric mill dynamics and its contribution to the dynamical bifurcation of the gastric mill and pyloric networks. We investigated the role of Ih in the rhythmic activity and cellular excitability of both the gastric mill neurons (medial gastric, gastric mill) and pyloric neurons (pyloric dilator, lateral pyloric) in Homarus americanus Through testing the burst period between 5 and 50 mM CsCl, and elimination of postinhibitory rebound and voltage sag, we found that 30 mM CsCl can sufficiently block Ih in both the pyloric and gastric mill neurons. Our results show that Ih maintains the excitability of both the pyloric and gastric mill neurons. However, Ih regulates slow oscillations of the pyloric and gastric mill neurons differently. Specifically, blocking Ih diminishes the difference between the pyloric and gastric mill burst periods by increasing the pyloric burst period and decreasing the gastric mill burst period. Moreover, the phase-plane analysis shows that blocking Ih causes the trajectory of slow oscillations of the gastric mill neurons to change toward the pyloric sinusoidal-like trajectories. In addition to regulating the pyloric rhythm, we found that Ih is also essential for the gastric mill rhythms and differentially regulates these two dynamics.

  18. Construction of a subtractive library from hexavalent chromium treated winter flounder (Pseudopleuronectes americanus) reveals alterations in non-selenium glutathione peroxidases.

    PubMed

    Chapman, Laura M; Roling, Jonathan A; Bingham, Lacey K; Herald, Matt R; Baldwin, William S

    2004-04-14

    Chromium is released during several industrial processes and has accumulated in some estuarine areas. Its effects on mammals have been widely studied, but relatively little information is available on its effects on fish. Gene expression changes are useful biomarkers that can provide information about toxicant exposure and effects, as well as the health of an organism and its ability to adapt to its surroundings. Therefore, we investigated the effects of Cr(VI) on gene expression in the sediment dwelling fish, winter flounder (Pseudopleuronectes americanus). Winter flounder ranging from 300 to 360 g were injected i.p. with Cr(VI) as chromium oxide at 25 microg/kg chromium in 0.15N KCl. Twenty-four hours following injections, winter flounder were euthanized with MS-222 and the livers were excised. Half of the livers were used to make cytosol and the other half were used to isolate mRNA for subtractive hybridization. Subtractive clones obtained were spotted onto nylon filters, which revealed several genes with potentially altered expression due to Cr(VI), including an alpha class GST, 1-Cys peroxiredoxin (a non-selenium glutathione peroxidase), a P-450 2X subfamily member, two elongation factors (EF-1 gamma and EF-2), and complement component C3. Semi-quantitative RT-PCR was performed and confirmed that Cr(VI) down-regulated complement component C3, an EST, and two potential glutathione peroxidases, GSTA3 and 1-Cys peroxiredoxin. In addition, cytosolic GSH peroxidase activity was reduced, and silver stained SDS-PAGE gels from glutathione-affinity purified cytosol demonstrated that a 27.1 kDa GSH-binding protein was down-regulated greater than 50%. Taken together, Cr(VI) significantly altered the expression of several genes including two potential glutathione peroxidases in winter flounder. PMID:15003702

  19. Substrate-Driven Convergence of the Microbial Community in Lignocellulose-Amended Enrichments of Gut Microflora from the Canadian Beaver (Castor canadensis) and North American Moose (Alces americanus).

    PubMed

    Wong, Mabel T; Wang, Weijun; Lacourt, Michael; Couturier, Marie; Edwards, Elizabeth A; Master, Emma R

    2016-01-01

    Strategic enrichment of microcosms derived from wood foragers can facilitate the discovery of key microbes that produce enzymes for the bioconversion of plant fiber (i.e., lignocellulose) into valuable chemicals and energy. In this study, lignocellulose-degrading microorganisms from the digestive systems of Canadian beaver (Castor canadensis) and North American moose (Alces americanus) were enriched under methanogenic conditions for over 3 years using various wood-derived substrates, including (i) cellulose (C), (ii) cellulose + lignosulphonate (CL), (iii) cellulose + tannic acid (CT), and (iv) poplar hydrolysate (PH). Substantial improvement in the conversion of amended organic substrates into biogas was observed in both beaver dropping and moose rumen enrichment cultures over the enrichment phases (up to 0.36-0.68 ml biogas/mg COD added), except for enrichments amended with tannic acid where conversion was approximately 0.15 ml biogas/mg COD added. Multiplex-pyrosequencing of 16S rRNA genes revealed systematic shifts in the population of Firmicutes, Bacteroidetes, Chlorobi, Spirochaetes, Chloroflexi, and Elusimicrobia in response to the enrichment. These shifts were predominantly substrate driven, not inoculum driven, as revealed by both UPGMA clustering pattern and OTU distribution. Additionally, the relative abundance of multiple OTUs from poorly defined taxonomic lineages increased from less than 1% to 25-50% in microcosms amended with lignocellulosic substrates, including OTUs from classes SJA-28, Endomicrobia, orders Bacteroidales, OPB54, and family Lachnospiraceae. This study provides the first direct comparison of shifts in microbial communities that occurred in different environmental samples in response to multiple relevant lignocellulosic carbon sources, and demonstrates the potential of enrichment to increase the abundance of key lignocellulolytic microorganisms and encoded activities.

  20. Isolation and Genetic Characterization of Toxoplasma gondii from Black Bears (Ursus americanus), Bobcats (Lynx rufus), and Feral Cats (Felis catus) from Pennsylvania.

    PubMed

    Dubey, Jitender P; Verma, Shiv K; Calero-Bernal, Rafael; Cassinelli, Ana B; Kwok, Oliver C H; Van Why, Kyle; Su, Chunlei; Humphreys, Jan G

    2015-01-01

    Toxoplasma gondii infects virtually all warm-blooded hosts worldwide. Recently, attention has been focused on the genetic diversity of the parasite to explain its pathogenicity in different hosts. It has been hypothesized that interaction between feral and domestic cycles of T. gondii may increase unusual genotypes in domestic cats and facilitate transmission of potentially more pathogenic genotypes to humans, domestic animals, and wildlife. In the present study, we tested black bear (Ursus americanus), bobcat (Lynx rufus), and feral cat (Felis catus) from the state of Pennsylvania for T. gondii infection. Antibodies to T. gondii were found in 32 (84.2%) of 38 bears, both bobcats, and 2 of 3 feral cats tested by the modified agglutination test (cut off titer 1:25). Hearts from seropositive animals were bioassayed in mice, and viable T. gondii was isolated from 3 of 32 bears, 2 of 2 bobcats, and 2 of 3 feral cats. DNA isolated from culture-derived tachyzoites of these isolates was characterized using multilocus PCR-RFLP markers. Three genotypes were revealed, including ToxoDB PCR-RFLP genotype #1 or #3 (Type II, 1 isolate), #5 (Type 12, 3 isolates), and #216 (3 isolates), adding to the evidence of genetic diversity of T. gondii in wildlife in Pennsylvania. Pathogenicity of 3 T. gondii isolates (all #216, 1 from bear, and 2 from feral cat) was determined in outbred Swiss Webster mice; all three were virulent causing 100% mortality. Results indicated that highly mouse pathogenic strains of T. gondii are circulating in wildlife, and these strains may pose risk to infect human through consuming of game meat.

  1. Influence of drift and admixture on population structure of American black bears (Ursus americanus) in the Central Interior Highlands, USA, 50 years after translocation.

    PubMed

    Puckett, Emily E; Kristensen, Thea V; Wilton, Clay M; Lyda, Sara B; Noyce, Karen V; Holahan, Paula M; Leslie, David M; Beringer, Jeff; Belant, Jerrold L; White, Don; Eggert, Lori S

    2014-05-01

    Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA, and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (AR = 9.11) and significantly lower in the translocated populations (AR = 7.07-7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (AR = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than either compared to the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pretranslocation remnant signature in Missouri but not in the Ouachitas.

  2. Development, characterisation, inheritance, and cross-species utility of American lobster (Homarus americanus) microsatellite and mtDNA PCR-RFLP markers.

    PubMed

    Jones, Matthew W; O'Reilly, Patrick T; McPherson, Arran A; McParland, Tara L; Armstrong, Dawn E; Cox, Andrea J; Spence, Koren R; Kenchington, Ellen L; Taggart, Chris T; Bentzen, Paul

    2003-02-01

    Effective management of exploited species demands contemporary knowledge of population structure and mating patterns. Genetic markers can prove useful in providing this knowledge. Despite its commercial importance, genetic markers for American lobster (Homarus americanus) are limited. We developed 12 tetra- and 1 trinucleotide microsatellite loci for American lobster that exhibit little stuttering after PCR amplification. Gene diversity of these loci ranged from 0.516 to 0.929. A four-locus multiplex permits rapid genotyping of progeny in parentage experiments with a paternity exclusion probability over the four loci of 97.8%. We examined the loci for conformity to Hardy-Weinberg expectations (HWE) and linkage using individuals from one location and found that four loci deviated from HWE. We also tested inheritance and pairwise linkage using 48 embryos from each of two females. With the exception of two loci that were derived from the same clone and separated by 72 bp, no evidence of linkage was found. We, for the first time, demonstrate the occurrence of multiple paternity in American lobster. We also observed an apparent occurrence of dispermic androgenesis, possibly the first documentation of such an event within a species. Ten of the loci amplified in European lobster (Homarus gammarus), although two were monomorphic and one deviated significantly from HWE. We quantified mitochondrial DNA (mtDNA) sequence variation through the use of PCR amplification of two DNA fragments, followed by digestion with restriction enzymes; eight haplotypes were detected. One of the two fragments amplified in European lobster. Both sets of markers should prove useful for population discrimination purposes, and the microsatellites, in particular the four-locus multiplex, should prove highly amenable to rapidly addressing questions about mating patterns. PMID:12669797

  3. A comparison of the structure of American (Homarus americanus) and European (Homarus gammarus) lobster cuticle with particular reference to shell disease susceptibility.

    PubMed

    Davies, Charlotte E; Whitten, Miranda M A; Kim, Anita; Wootton, Emma C; Maffeis, Thierry G G; Tlusty, Michael; Vogan, Claire L; Rowley, Andrew F

    2014-03-01

    The integument of arthropods is an important first-line defence against the invasion of parasites and pathogens. Once damaged, this can be subject to colonisation by microbial agents from the surrounding environment, which in crustaceans can lead to a condition termed shell disease syndrome. This condition has been reported in several crustacean species, including crabs and lobsters. The syndrome is a progressive condition where the outer cuticle becomes pitted and eroded, and in extreme cases is compromised, leaving animals susceptible to septicaemia. This study examined the susceptibility of juvenile American (Homarus americanus) and European (Homarus gammarus) lobsters to shell disease, as a result of mechanical damage. Scanning electron microscopy was used as a method to identify differences in the cuticle structure and consequences of mechanical damage. Claw regions were aseptically punctured, whilst carapaces were abraded using sterile sandpaper, to mimic natural damage. After a period of between 10 and 12 weeks, lobsters were sacrificed, fixed and stored for later examination. The carapace and claws of juvenile American lobsters were shown to be thinner and more vulnerable to abrasion damage than their European counterparts. In addition, the number and distribution of setal pits and pore canal openings also differed between the two species of lobster. Mechanical damage resulted in the formation of shell disease lesions on the claw and carapace of both lobster species. However, American lobsters, unlike their European counterparts, had extensive bacterial colonisation on the margins of these lesions. Overall, it is concluded that the cuticle of the American lobster is more susceptible to damage and resulting microbial colonisation. This may have implications for susceptibility of both species of lobster to shell disease syndrome. PMID:24468664

  4. RAD genotyping reveals fine-scale genetic structuring and provides powerful population assignment in a widely distributed marine species, the American lobster (Homarus americanus).

    PubMed

    Benestan, Laura; Gosselin, Thierry; Perrier, Charles; Sainte-Marie, Bernard; Rochette, Rémy; Bernatchez, Louis

    2015-07-01

    Deciphering genetic structure and inferring connectivity in marine species have been challenging due to weak genetic differentiation and limited resolution offered by traditional genotypic methods. The main goal of this study was to assess how a population genomics framework could help delineate the genetic structure of the American lobster (Homarus americanus) throughout much of the species' range and increase the assignment success of individuals to their location of origin. We genotyped 10 156 filtered SNPs using RAD sequencing to delineate genetic structure and perform population assignment for 586 American lobsters collected in 17 locations distributed across a large portion of the species' natural distribution range. Our results revealed the existence of a hierarchical genetic structure, first separating lobsters from the northern and southern part of the range (FCT  = 0.0011; P-value = 0.0002) and then revealing a total of 11 genetically distinguishable populations (mean FST  = 0.00185; CI: 0.0007-0.0021, P-value < 0.0002), providing strong evidence for weak, albeit fine-scale population structuring within each region. A resampling procedure showed that assignment success was highest with a subset of 3000 SNPs having the highest FST . Applying Anderson's (Molecular Ecology Resources, 2010, 10, 701) method to avoid 'high-grading bias', 94.2% and 80.8% of individuals were correctly assigned to their region and location of origin, respectively. Lastly, we showed that assignment success was positively associated with sample size. These results demonstrate that using a large number of SNPs improves fine-scale population structure delineation and population assignment success in a context of weak genetic structure. We discuss the implications of these findings for the conservation and management of highly connected marine species, particularly regarding the geographic scale of demographic independence.

  5. A comparison of the structure of American (Homarus americanus) and European (Homarus gammarus) lobster cuticle with particular reference to shell disease susceptibility.

    PubMed

    Davies, Charlotte E; Whitten, Miranda M A; Kim, Anita; Wootton, Emma C; Maffeis, Thierry G G; Tlusty, Michael; Vogan, Claire L; Rowley, Andrew F

    2014-03-01

    The integument of arthropods is an important first-line defence against the invasion of parasites and pathogens. Once damaged, this can be subject to colonisation by microbial agents from the surrounding environment, which in crustaceans can lead to a condition termed shell disease syndrome. This condition has been reported in several crustacean species, including crabs and lobsters. The syndrome is a progressive condition where the outer cuticle becomes pitted and eroded, and in extreme cases is compromised, leaving animals susceptible to septicaemia. This study examined the susceptibility of juvenile American (Homarus americanus) and European (Homarus gammarus) lobsters to shell disease, as a result of mechanical damage. Scanning electron microscopy was used as a method to identify differences in the cuticle structure and consequences of mechanical damage. Claw regions were aseptically punctured, whilst carapaces were abraded using sterile sandpaper, to mimic natural damage. After a period of between 10 and 12 weeks, lobsters were sacrificed, fixed and stored for later examination. The carapace and claws of juvenile American lobsters were shown to be thinner and more vulnerable to abrasion damage than their European counterparts. In addition, the number and distribution of setal pits and pore canal openings also differed between the two species of lobster. Mechanical damage resulted in the formation of shell disease lesions on the claw and carapace of both lobster species. However, American lobsters, unlike their European counterparts, had extensive bacterial colonisation on the margins of these lesions. Overall, it is concluded that the cuticle of the American lobster is more susceptible to damage and resulting microbial colonisation. This may have implications for susceptibility of both species of lobster to shell disease syndrome.

  6. Influence of drift and admixture on population structure of American black bears (Ursus americanus) in the Central Interior Highlands, USA, 50 years after translocation.

    PubMed

    Puckett, Emily E; Kristensen, Thea V; Wilton, Clay M; Lyda, Sara B; Noyce, Karen V; Holahan, Paula M; Leslie, David M; Beringer, Jeff; Belant, Jerrold L; White, Don; Eggert, Lori S

    2014-05-01

    Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA, and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (AR = 9.11) and significantly lower in the translocated populations (AR = 7.07-7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (AR = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than either compared to the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pretranslocation remnant signature in Missouri but not in the Ouachitas. PMID:24712442

  7. Discovery and description of a new trichostrongyloid species (Nematoda: Ostertagiinae), abomasal parasites in mountain goat, Oreamnos americanus, from the Western Cordillera of North America.

    PubMed

    Hoberg, Eric P; Abrams, Arthur; Pilitt, Patricia A; Jenkins, Emily J

    2012-08-01

    Marshallagia lichtenfelsi sp. n. is a dimorphic ostertagiine nematode occurring in the abomasum of mountain goats, Oreamnos americanus, from the Western Cordillera of North America. Major and minor morphotype males and females are characterized and distinguished relative to the morphologically similar Marshallagia marshalli / Marshallagia occidentalis from North America and Marshallagia dentispicularis, along with other congeners, from the Palearctic region. The configuration of the convoluted and irregular synlophe in the cervical region of males and females of M. lichtenfelsi is apparently unique, contrasting with a continuous and parallel system of ridges among those species of Marshallagia, including M. marshalli/M. occidentalis, which have been evaluated. Specimens of M. lichtenfelsi are further defined by the rectangular form of the accessory bursal membrane (width > length) in the major morphotype and by the trapezoidal Sjöberg's organ in the minor morphotype, in addition to specific attributes of the spicules and spicule tips. We regard 12 species, including the proposed new taxon, to be valid. Primary diagnostic characters are reviewed for Marshallagia and a framework is presented for standardization of future descriptions incorporating the synlophe in males and females and the structure of the spicules and genital cone in major and minor morphotype males. The center of diversity for species of Marshallagia is the mountain-steppe region of central Eurasia where 11 species (including the Holarctic M. marshalli) are recognized in association with Caprini, Rupicaprini, and Antelopinae; only 2 species occur in the Nearctic. In this assemblage, M. lichtenfelsi is endemic to North America and limited in host distribution to mountain goats. An intricate history for refugial isolation and population fragmentation demonstrated for mountain goats and wild sheep indicates the potential for considerable cryptic diversity for Marshallagia and other nematodes. Shifting

  8. Serological survey of selected canine viral pathogens and zoonoses in grizzly bears (Ursus arctos horribilis) and black bears (Ursus americanus) from Alaska.

    PubMed

    Chomel, B B; Kasten, R W; Chappuis, G; Soulier, M; Kikuchi, Y

    1998-12-01

    Between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (Ursus arctos horribilis) and 40 black bears (Ursus americanus) from Alaska, United States of America, and were tested for selected canine viral infections and zoonoses. Antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. In black bears, prevalence ranged from 0% for distemper and parvovirus to 27.5% for trichinellosis and 32% for tularaemia. Antibody prevalence for brucellosis (2.5%) and tularaemia (32%) were identical for grizzly bears and black bears from the geographical area of interior Alaska. Links between differences in prevalence and the origin of the grizzly bears were observed. Antibodies to canine distemper virus and infectious hepatitis virus were mainly detected in grizzly bears from Kodiak Island and the Alaskan Peninsula. Brucellosis antibodies were prevalent in grizzly bears from western and northern Alaska, whereas tularaemia antibodies were detected in grizzly bears from interior Alaska and the Arctic. There was a strong gradient for antibodies to Trichinella spp. from southern to northern Alaska. For most diseases, antibody prevalence increased with age. However, for several infections, no antibodies were detected in grizzly bears aged from 0 to 2 years, in contrast to the presence of those infections in black bears. Grizzly bears served as excellent sentinels for surveillance of zoonotic infections in wildlife in Alaska.

  9. Influence of drift and admixture on population structure of American black bears (Ursus americanus) in the Central Interior Highlands, USA, 50 years after translocation

    USGS Publications Warehouse

    Puckett, Emily E.; Kristensen, Thea V.; Wilton, Clay M.; Lyda, Sara B.; Noyce, Karen V.; Holahan, Paula M.; Leslie,, David M.; Beringer, J.; Belant, Jerrold L.; White, D.; Eggert, L.S.

    2014-01-01

    Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA, and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (AR = 9.11) and significantly lower in the translocated populations (AR = 7.07-7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (AR = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than either compared to the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pretranslocation remnant signature in Missouri but not in the Ouachitas.

  10. Repetitive DNA chromosomal organization in the cricket Cycloptiloides americanus: a case of the unusual X1X 20 sex chromosome system in Orthoptera.

    PubMed

    Palacios-Gimenez, Octavio M; Cabral-de-Mello, Diogo C

    2015-04-01

    A common placement for most sex chromosomes that is involved in their evolutionary histories is the accumulation of distinct classes of repetitive DNAs. Here, with the aim of understanding the poorly studied repetitive DNA organization in crickets and its possible role in sex chromosome differentiation, we characterized the chromosomes of the cricket species Cycloptiloides americanus, a species with the remarkable presence of the unusual sex chromosome system X1X20♂/X1X1X2X2♀. For these proposes, we used C-banding and mapping through the fluorescence in situ hybridization of some repetitive DNAs. The C-banding and distribution of highly and moderately repetitive DNAs (C 0t-1 DNA) varied depending of the chromosome. The greater accumulation of repetitive DNAs in the X2 chromosome was evidenced. The microsatellites were spread along entire chromosomes, but (AG)10 and (TAA)10 were less enriched, mainly in the centromeric areas. Among the multigene families, the 18S rDNA was spread throughout almost all of the chromosomes, except for pair 5 and X2, while the U2 snDNA was placed exclusively in the largest chromosome. Finally, the 5S rDNA was exclusively located in the short arms of the sex chromosomes. The obtained data reinforce the importance of chromosomal dissociation and inversion as a primary evolutionary mechanism to generate neo-sex chromosomes in the species studied, followed by the repetitive DNAs accumulation. Moreover the exclusive placement of 5S rDNA in the sex chromosomes suggests the involvement of this sequence in sex chromosome recognition throughout meiosis and, consequently, their maintenance, in addition to their avoiding degeneration.

  11. Role of Ih in differentiating the dynamics of the gastric and pyloric neurons in the stomatogastric ganglion of the lobster, Homarus americanus.

    PubMed

    Zhu, Lin; Selverston, Allen I; Ayers, Joseph

    2016-06-01

    The hyperpolarization-activated inward cationic current (Ih) is known to regulate the rhythmicity, excitability, and synaptic transmission in heart cells and many types of neurons across a variety of species, including some pyloric and gastric mill neurons in the stomatogastric ganglion (STG) in Cancer borealis and Panulirus interruptus However, little is known about the role of Ih in regulating the gastric mill dynamics and its contribution to the dynamical bifurcation of the gastric mill and pyloric networks. We investigated the role of Ih in the rhythmic activity and cellular excitability of both the gastric mill neurons (medial gastric, gastric mill) and pyloric neurons (pyloric dilator, lateral pyloric) in Homarus americanus Through testing the burst period between 5 and 50 mM CsCl, and elimination of postinhibitory rebound and voltage sag, we found that 30 mM CsCl can sufficiently block Ih in both the pyloric and gastric mill neurons. Our results show that Ih maintains the excitability of both the pyloric and gastric mill neurons. However, Ih regulates slow oscillations of the pyloric and gastric mill neurons differently. Specifically, blocking Ih diminishes the difference between the pyloric and gastric mill burst periods by increasing the pyloric burst period and decreasing the gastric mill burst period. Moreover, the phase-plane analysis shows that blocking Ih causes the trajectory of slow oscillations of the gastric mill neurons to change toward the pyloric sinusoidal-like trajectories. In addition to regulating the pyloric rhythm, we found that Ih is also essential for the gastric mill rhythms and differentially regulates these two dynamics. PMID:26912595

  12. RAD genotyping reveals fine-scale genetic structuring and provides powerful population assignment in a widely distributed marine species, the American lobster (Homarus americanus).

    PubMed

    Benestan, Laura; Gosselin, Thierry; Perrier, Charles; Sainte-Marie, Bernard; Rochette, Rémy; Bernatchez, Louis

    2015-07-01

    Deciphering genetic structure and inferring connectivity in marine species have been challenging due to weak genetic differentiation and limited resolution offered by traditional genotypic methods. The main goal of this study was to assess how a population genomics framework could help delineate the genetic structure of the American lobster (Homarus americanus) throughout much of the species' range and increase the assignment success of individuals to their location of origin. We genotyped 10 156 filtered SNPs using RAD sequencing to delineate genetic structure and perform population assignment for 586 American lobsters collected in 17 locations distributed across a large portion of the species' natural distribution range. Our results revealed the existence of a hierarchical genetic structure, first separating lobsters from the northern and southern part of the range (FCT  = 0.0011; P-value = 0.0002) and then revealing a total of 11 genetically distinguishable populations (mean FST  = 0.00185; CI: 0.0007-0.0021, P-value < 0.0002), providing strong evidence for weak, albeit fine-scale population structuring within each region. A resampling procedure showed that assignment success was highest with a subset of 3000 SNPs having the highest FST . Applying Anderson's (Molecular Ecology Resources, 2010, 10, 701) method to avoid 'high-grading bias', 94.2% and 80.8% of individuals were correctly assigned to their region and location of origin, respectively. Lastly, we showed that assignment success was positively associated with sample size. These results demonstrate that using a large number of SNPs improves fine-scale population structure delineation and population assignment success in a context of weak genetic structure. We discuss the implications of these findings for the conservation and management of highly connected marine species, particularly regarding the geographic scale of demographic independence. PMID:25977167

  13. Simulations of Atmospheric Neutral Wave Coupling to the Ionosphere

    NASA Astrophysics Data System (ADS)

    Siefring, C. L.; Bernhardt, P. A.

    2005-12-01

    The densities in the E- and F-layer plasmas are much less than the density of background neutral atmosphere. Atmospheric neutral waves are primary sources of plasma density fluctuations and are the sources for triggering plasma instabilities. The neutral atmosphere supports acoustic waves, acoustic gravity waves, and Kelvin Helmholtz waves from wind shears. These waves help determine the structure of the ionosphere by changes in neutral density that affect ion-electron recombination and by neutral velocities that couple to the plasma via ion-neutral collisions. Neutral acoustic disturbances can arise from thunderstorms, chemical factory explosions and intentional high-explosive tests. Based on conservation of energy, acoustic waves grow in amplitude as they propagate upwards to lower atmospheric densities. Shock waves can form in an acoustic pulse that is eventually damped by viscosity. Ionospheric effects from acoustic waves include transient perturbations of E- and F-Regions and triggering of E-Region instabilities. Acoustic-gravity waves affect the ionosphere over large distances. Gravity wave sources include thunderstorms, auroral region disturbances, Space Shuttle launches and possibly solar eclipses. Low frequency acoustic-gravity waves propagate to yield traveling ionospheric disturbances (TID's), triggering of Equatorial bubbles, and possible periodic structuring of the E-Region. Gravity wave triggering of equatorial bubbles is studied numerically by solving the equations for plasma continuity and ion velocity along with Ohms law to provide an equation for the induced electric potential. Slow moving gravity waves provide density depressions on bottom of ionosphere and a gravitational Rayleigh-Taylor instability is initiated. Radar scatter detects field aligned irregularities in the resulting plasma bubble. Neutral Kelvin-Helmholtz waves are produced by strong mesospheric wind shears that are also coincident with the formation of intense E-layers. An

  14. BEAMS3D Neutral Beam Injection Model

    SciTech Connect

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.

  15. Molecular clock on a neutral network.

    PubMed

    Raval, Alpan

    2007-09-28

    The number of fixed mutations accumulated in an evolving population often displays a variance that is significantly larger than the mean (the overdispersed molecular clock). By examining a generic evolutionary process on a neutral network of high-fitness genotypes, we establish a formalism for computing all cumulants of the full probability distribution of accumulated mutations in terms of graph properties of the neutral network, and use the formalism to prove overdispersion of the molecular clock. We further show that significant overdispersion arises naturally in evolution when the neutral network is highly sparse, exhibits large global fluctuations in neutrality, and small local fluctuations in neutrality. The results are also relevant for elucidating aspects of neutral network topology from empirical measurements of the substitution process.

  16. Structure of Rotavirus Outer-Layer Protein VP7 Bound with a Neutralizing Fab

    SciTech Connect

    Aoki, Scott T.; Settembre, Ethan C.; Trask, Shane D.; Greenberg, Harry B.; Harrison, Stephen C.; Dormitzer, Philip R.

    2009-06-17

    Rotavirus outer-layer protein VP7 is a principal target of protective antibodies. Removal of free calcium ions (Ca{sup 2+}) dissociates VP7 trimers into monomers, releasing VP7 from the virion, and initiates penetration-inducing conformational changes in the other outer-layer protein, VP4. We report the crystal structure at 3.4 angstrom resolution of VP7 bound with the Fab fragment of a neutralizing monoclonal antibody. The Fab binds across the outer surface of the intersubunit contact, which contains two Ca{sup 2+} sites. Mutations that escape neutralization by other antibodies suggest that the same region bears the epitopes of most neutralizing antibodies. The monovalent Fab is sufficient to neutralize infectivity. We propose that neutralizing antibodies against VP7 act by stabilizing the trimer, thereby inhibiting the uncoating trigger for VP4 rearrangement. A disulfide-linked trimer is a potential subunit immunogen.

  17. On some mites (Acari: Prostigmata) from the Interior Highlands: descriptions of the male, immature stages, and female reproductive system of Pseudocheylus americanus (Ewing, 1909) and some new state records for Arkansas.

    PubMed

    Skvarla, Michael J; Fisher, J Ray; Dowling, Ashley P G

    2013-01-01

    The male and immature stages of Pseudocheylus americanus (Ewing, 1909) (Pseudocheylidae) are described and illustrated for the first time and the female is re-illustrated. The description of Pseudobonzia reticulata (Heryford, 1965) (Cunaxidae) is modified to include the presence of dorsal setae f2, which were not reported in the original description. In addition, Bonzia yunkeri Smiley, 1992 and Parabonzia bdelliforimis (Atyeo, 1958) (Cunaxidae) are reported from the Ozark Mountains, Caeculus cremnicolus Enns, 1958 (Caeculidae) is reported from the Ozark and Ouachita Mountains, and Dasythyreus hirsutus Atyeo, 1961 (Dasythyreidae) is reported from Missouri and the Ouachita Mountains in Arkansas.

  18. Progressive Hemorrhage and Myotoxicity Induced by Echis carinatus Venom in Murine Model: Neutralization by Inhibitor Cocktail of N,N,N',N'-Tetrakis (2-Pyridylmethyl) Ethane-1,2-Diamine and Silymarin

    PubMed Central

    Nanjaraj Urs, Ankanahalli N.; Ramakrishnan, Chandrasekaran; Joshi, Vikram; Suvilesh, Kanve Nagaraj; Veerabasappa Gowda, Teregowda; Velmurugan, Devadasan; Vishwanath, Bannikuppe Sannanaik

    2015-01-01

    Viperbite is often associated with severe local toxicity, including progressive hemorrhage and myotoxicity, persistent even after the administration of anti-snake venom (ASV). In the recent past, investigations have revealed the orchestrated actions of Zn2+ metalloproteases (Zn2+MPs), phospholipase A2s (PLA2s) and hyaluronidases (HYs) in the onset and progression of local toxicity from the bitten site. As a consequence, venom researchers and medical practitioners are in deliberate quest of potent molecules alongside ASV to tackle the brutal local manifestations induced by aforesaid venom toxins. Based on these facts, we have demonstrated the protective efficacy of inhibitor cocktail containing equal ratios of N,N,N’,N’-tetrakis (2-pyridylmethyl) ethane-1,2-diamine (TPEN) and silymarin (SLN) against progressive local toxicity induced by Echis carinatus venom (ECV). In our previous study we have shown the inhibitory potentials of TPEN towards Zn2+MPs of ECV (IC50: 6.7 μM). In this study we have evaluated in vitro inhibitory potentials of SLN towards PLA2s (IC50: 12.5 μM) and HYs (IC50: 8 μM) of ECV in addition to docking studies. Further, we have demonstrated the protection of ECV induced local toxicity with 10 mM inhibitor cocktail following 15, 30 min (for hemorrhage and myotoxicity); 60 min (for hemorrhage alone) of ECV injection in murine model. The histological examination of skin and thigh muscle sections taken out from the site of ECV injection substantiated the overall protection offered by inhibitor cocktail. In conclusion, the protective efficacy of inhibitor cocktail is of high interest and can be administered locally alongside ASV to treat severe local toxicity. PMID:26274501

  19. Neutral Vlasov kinetic theory of magnetized plasmas

    SciTech Connect

    Tronci, Cesare; Camporeale, Enrico

    2015-02-15

    The low-frequency limit of Maxwell equations is considered in the Maxwell-Vlasov system. This limit produces a neutral Vlasov system that captures essential features of plasma dynamics, while neglecting radiation effects. Euler-Poincaré reduction theory is used to show that the neutral Vlasov kinetic theory possesses a variational formulation in both Lagrangian and Eulerian coordinates. By construction, the new model recovers all collisionless neutral models employed in plasma simulations. Then, comparisons between the neutral Vlasov system and hybrid kinetic-fluid models are presented in the linear regime.

  20. EFFECTS OF LEAKAGE NEUTRAL PARTICLES ON SHOCKS

    SciTech Connect

    Ohira, Yutaka

    2012-10-20

    In this paper, we investigate effects of neutral particles on shocks propagating into the partially ionized medium. We find that for 120 km s{sup -1} < u {sub sh} < 3000 km s{sup -1} (u {sub sh} is the shock velocity), about 10% of upstream neutral particles leak into the upstream region from the downstream region. Moreover, we investigate how the leakage neutral particles affect the upstream structure of the shock and particle accelerations. Using four-fluid approximations (upstream ions, upstream neutral particles, leakage neutral particles, and pickup ions), we provide analytical solutions of the precursor structure due to leakage neutral particles. It is shown that the upstream flow is decelerated in the precursor region and the shock compression ratio becomes smaller than without leakage neutral particles, but the total compression ratio does not change. Even if leakage of neutral particles is small (a few percent of total upstream particles), this smaller compression ratio of the shock can explain steep gamma-ray spectra from young supernova remnants. Furthermore, leakage neutral particles could amplify the magnetic field and heat the upstream region.