573 research outputs found

    Characterization of a Granulovirus Isolated from Epinotia aporema Wals. (Lepidoptera: Tortricidae) Larvae

    Get PDF
    A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae) - a major soybean pest - was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.Facultad de Ciencias ExactasInstituto de Biotecnologia y Biologia Molecula

    Characterization of a Granulovirus Isolated from Epinotia aporema Wals. (Lepidoptera: Tortricidae) Larvae

    Get PDF
    A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae) - a major soybean pest - was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.Facultad de Ciencias ExactasInstituto de Biotecnologia y Biologia Molecula

    Incidence and Duration of Type-Specific Human Papillomavirus Infection in High-Risk HPV-Naïve Women: Results from the Control Arm of a Phase II HPV-16/18 Vaccine Trial

    Get PDF
    OBJECTIVES: Persistence of human papillomaviruses (HPVs) is necessary for cervical carcinogenesis. We evaluated incidence and duration of type-specific HPV infections and the influence of age and number of sexual partners. METHODS: Data were obtained from 553 women (15-25 years), who were seronegative and DNA-negative for high-risk HPV (HR-HPV) types and were enrolled in the placebo arm of a randomised trial of the HPV-16/18 vaccine (NCT00689741/NCT00120848). They were followed for 6.3 years. Cervicovaginal samples were self-collected at 3-month intervals for up to 27 months, and cervical samples were collected by clinicians at 6-month intervals until study end. Samples were tested for HPV types using a broad-spectrum PCR assay. Incidence rate ratios (RRs) and 95% CIs were used to estimate the association among age, sexual habits and HPV acquisition. RESULTS: Incidence rates (95% CI) using cervical samples were 11.8 (10.4 to 13.4) and 5.6 (4.7 to 6.6) per 1000 women-months for HR-HPVs and low-risk HPVs (LR-HPVs), respectively. Equivalent rates in combined cervicovaginal and cervical samples were 17.2 (15.4 to 19.2) and 6.9 (5.9 to 8.0), respectively. 54 per cent of HR-HPV types from combined cervicovaginal and cervical samples persisted for 1 year compared with 32.3% for LR-HPV types. The risk of acquiring any HPV infection was higher among women aged(RR=1.33, 95% CI 1.1 to 1.7) and women having \u3e1 sexual partner (RR=1.83, 95% CI 1.4 to 2.4) at baseline. CONCLUSIONS: HR-HPV infections were more common and lasted longer on average than LR-HPV infections. HPV acquisition was more common in younger women with multiple sexual partners

    Anti-cancer effects and mechanism of actions of aspirin analogues in the treatment of glioma cancer

    Get PDF
    INTRODUCTION: In the past 25 years only modest advancements in glioma treatment have been made, with patient prognosis and median survival time following diagnosis only increasing from 3 to 7 months. A substantial body of clinical and preclinical evidence has suggested a role for aspirin in the treatment of cancer with multiple mechanisms of action proposed including COX 2 inhibition, down regulation of EGFR expression, and NF-κB signaling affecting Bcl-2 expression. However, with serious side effects such as stroke and gastrointestinal bleeding, aspirin analogues with improved potency and side effect profiles are being developed. METHOD: Effects on cell viability following 24 hr incubation of four aspirin derivatives (PN508, 517, 526 and 529) were compared to cisplatin, aspirin and di-aspirin in four glioma cell lines (U87 MG, SVG P12, GOS – 3, and 1321N1), using the PrestoBlue assay, establishing IC50 and examining the time course of drug effects. RESULTS: All compounds were found to decrease cell viability in a concentration and time dependant manner. Significantly, the analogue PN517 (IC50 2mM) showed approximately a twofold increase in potency when compared to aspirin (3.7mM) and cisplatin (4.3mM) in U87 cells, with similar increased potency in SVG P12 cells. Other analogues demonstrated similar potency to aspirin and cisplatin. CONCLUSION: These results support the further development and characterization of novel NSAID derivatives for the treatment of glioma

    Limits on neutrino oscillations from ν̄e appearance

    Get PDF
    A 20-ton neutrino detector located near the Los Alamos Meson Physics Facility beam stop is used search for ν̄e generated via neutrino oscillations from any of the three neutrino types, νμ, ν̄μ, and νe, which radiate from the beam stop. The analysis of three years of data provides limits on the oscillation modes ν̄μ→ν̄e, νe→ν̄e, and νμ→ν̄e, and the lepton-number-violating decay process μ+→e++ν̄e+νμ. The 90%-confidence-level limits for ν̄μ→ν̄e oscillations are δm2≤0.14 eV2 for maximal mixing, and sin22θ≤0.024 for large δm2. © 1993 The American Physical Society

    A rise in the frequency of lasR mutant Pseudomonas aeruginosa among keratitis isolates between 1993 and 2021

    Get PDF
    IntroductionPseudomonas aeruginosa causes vision threatening keratitis. The LasR transcription factor regulates virulence factors in response to the quorum sensing molecule N-3-oxo-dodecanoyl-L-homoserine lactone. P. aeruginosa isolates with lasR mutations are characterized by an iridescent high sheen phenotype caused by a build-up of 2-heptyl-4-quinolone. A previous study demonstrated 22% (n=101) of P. aeruginosa keratitis isolates from India between 2010 and 2016 were sheen positive lasR mutants, and the sheen phenotype correlated with worse clinical outcomes for patients. In this study, a longitudinal collection of P. aeruginosa keratitis isolates from Eastern North America were screened for lasR mutations by the sheen phenotype and sequencing of the lasR gene.MethodsKeratitis isolates (n=399) were classified by sheen phenotype. The lasR gene was cloned from a subset of isolates, sequenced, and tested for loss of function or dominant-negative status based on an azocasein protease assay. A retrospective chart review compared outcomes of keratitis patients infected by sheen positive and negative isolates.ResultsA significant increase in sheen positive isolates was observed between 1993 and 2021. Extracellular protease activity was reduced among the sheen positive isolates and a defined lasR mutant. Cloned lasR alleles from the sheen positive isolates were loss of function or dominant negative and differed in sequence from previously reported ocular lasR mutant alleles. Retrospective analysis of patient information suggested significantly better visual outcomes for patients infected by sheen positive isolates.DiscussionThese results indicate an increase in lasR mutations among keratitis isolates in the United States and suggest that endemic lasR mutants can cause keratitis

    Measurement of inclusive D*+- and associated dijet cross sections in photoproduction at HERA

    Get PDF
    Inclusive photoproduction of D*+- mesons has been measured for photon-proton centre-of-mass energies in the range 130 < W < 280 GeV and a photon virtuality Q^2 < 1 GeV^2. The data sample used corresponds to an integrated luminosity of 37 pb^-1. Total and differential cross sections as functions of the D* transverse momentum and pseudorapidity are presented in restricted kinematical regions and the data are compared with next-to-leading order (NLO) perturbative QCD calculations using the "massive charm" and "massless charm" schemes. The measured cross sections are generally above the NLO calculations, in particular in the forward (proton) direction. The large data sample also allows the study of dijet production associated with charm. A significant resolved as well as a direct photon component contribute to the cross section. Leading order QCD Monte Carlo calculations indicate that the resolved contribution arises from a significant charm component in the photon. A massive charm NLO parton level calculation yields lower cross sections compared to the measured results in a kinematic region where the resolved photon contribution is significant.Comment: 32 pages including 6 figure

    Measurement of the diffractive structure function in deep inelastic scattering at HERA

    Full text link
    This paper presents an analysis of the inclusive properties of diffractive deep inelastic scattering events produced in epep interactions at HERA. The events are characterised by a rapidity gap between the outgoing proton system and the remaining hadronic system. Inclusive distributions are presented and compared with Monte Carlo models for diffractive processes. The data are consistent with models where the pomeron structure function has a hard and a soft contribution. The diffractive structure function is measured as a function of \xpom, the momentum fraction lost by the proton, of β\beta, the momentum fraction of the struck quark with respect to \xpom, and of Q2Q^2. The \xpom dependence is consistent with the form \xpoma where a = 1.30 ± 0.08 (stat)  0.14+ 0.08 (sys)a~=~1.30~\pm~0.08~(stat)~^{+~0.08}_{-~0.14}~(sys) in all bins of β\beta and Q2Q^2. In the measured Q2Q^2 range, the diffractive structure function approximately scales with Q2Q^2 at fixed β\beta. In an Ingelman-Schlein type model, where commonly used pomeron flux factor normalisations are assumed, it is found that the quarks within the pomeron do not saturate the momentum sum rule.Comment: 36 pages, latex, 11 figures appended as uuencoded fil

    Measurement of Jet Shapes in Photoproduction at HERA

    Full text link
    The shape of jets produced in quasi-real photon-proton collisions at centre-of-mass energies in the range 134277134-277 GeV has been measured using the hadronic energy flow. The measurement was done with the ZEUS detector at HERA. Jets are identified using a cone algorithm in the ηϕ\eta - \phi plane with a cone radius of one unit. Measured jet shapes both in inclusive jet and dijet production with transverse energies ETjet>14E^{jet}_T>14 GeV are presented. The jet shape broadens as the jet pseudorapidity (ηjet\eta^{jet}) increases and narrows as ETjetE^{jet}_T increases. In dijet photoproduction, the jet shapes have been measured separately for samples dominated by resolved and by direct processes. Leading-logarithm parton-shower Monte Carlo calculations of resolved and direct processes describe well the measured jet shapes except for the inclusive production of jets with high ηjet\eta^{jet} and low ETjetE^{jet}_T. The observed broadening of the jet shape as ηjet\eta^{jet} increases is consistent with the predicted increase in the fraction of final state gluon jets.Comment: 29 pages including 9 figure

    Measuring and modelling the response of Klebsiella pneumoniae KPC prey to Bdellovibrio bacteriovorus predation, in human serum and defined buffer

    Get PDF
    In worldwide conditions of increasingly antibiotic-resistant hospital infections, it is important to research alternative therapies. Bdellovibrio bacteriovorus bacteria naturally prey on Gram-negative pathogens, including antibiotic-resistant strains and so B. bacteriovorus have been proposed as "living antibiotics" to combat antimicrobially-resistant pathogens. Predator-prey interactions are complex and can be altered by environmental components. To be effective B. bacteriovorus predation needs to work in human body fluids such as serum where predation dynamics may differ to that studied in laboratory media. Here we combine mathematical modelling and lab experimentation to investigate the predation of an important carbapenem-resistant human pathogen, Klebsiella pneumoniae, by B. bacteriovorus in human serum versus buffer. We show experimentally that B. bacteriovorus is able to reduce prey numbers in each environment, on different timescales. Our mathematical model captures the underlying dynamics of the experimentation, including an initial predation-delay at the predator-prey-serum interface. Our research shows differences between predation in buffer and serum and highlights both the potential and limitations of B. bacteriovorus acting therapeutically against K. pneumoniae in serum, informing future research into the medicinal behaviours and dosing of this living antibacterial
    corecore