170 research outputs found

    Detection of Recent HIV-1 Infection Using a New Limiting-Antigen Avidity Assay: Potential for HIV-1 Incidence Estimates and Avidity Maturation Studies

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    Background: Accurate and reliable laboratory methods are needed for estimation of HIV-1 incidence to identify the highrisk populations and target and monitor prevention efforts. We previously described a single-well limiting-antigen avidity enzyme immunoassay (LAg-Avidity EIA) to detect recent HIV-1 infection. Methods: We describe here further optimization and characterization of LAg-Avidity EIA, comparing it to the BED assay and a two-well avidity-index (AI) EIA. Specimen sets included longitudinal sera (n = 393), collected from 89 seroconverting individuals from 4 cohorts representing 4 HIV-1 subtypes, and sera from AIDS patients (n = 488) with or without TB coinfections from 3 different cohorts. Ninety seven HIV-1 positive specimens were purchased commercially. The BED assay, LAg-Avidity EIA, AI-EIA and HIV serology were performed, as needed. Results: Monitoring quality control specimens indicated high reproducibility of the LAg-Avidity EIA with coefficient of variation of,10 % in the dynamic range. The LAg-Avidity EIA has an overall mean duration of recency (v) of 141 days (95% CI 119–160) at normalized optical density (ODn) cutoff of 1.0, with similar v in different HIV-1 subtypes and populations (132 to 143 days). Antibody avidity kinetics were similar among individuals and subtypes by both the LAg-Avidity EIA and AI-EIA compared to the HIV-IgG levels measured by the BED assay. The false recent rate among individuals with AIDS was 0.2% with the LAg-Avidity EIA, compared to 2.9 % with the BED assay. Western blot profiles of specimens with increasing avidit

    The asymmetric aza-silyl-prins reaction: Synthesis of enantiopure piperidines

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    The design and development of the first asymmetric aza-silyl-Prins reaction is reported, giving rise to valuable and diverse piperidines and pipecolic acid derivatives in both high yields and as single enantiomers. The creation of a novel chiral auxiliary-homoallylic amine for the aza-silyl-Prins reaction is essential to its success

    First draft genome and transcriptome of \u3ci\u3eCercosporidium personatum\u3c/i\u3e, causal agent of late leaf spot disease of peanut

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    Objective Two main fungal leaf spot diseases occur in peanut, namely early leaf spot (ELS) and late leaf spot (LLS), these cause a yearly average of $44 million losses. Limited genetic information, 3534 bp of sequencing, exists about the causal agent of LLS, Cercosporidium personatum (syn. Nothopassalora personata, syn. Phaeoisariopsis personata). The extremely slow growth of this fungus, approximately 1 cm colony in 6 months, and challenges in nucleic acid extractions have hindered research on LLS. Our goal in this work is to provide a reference genome for research on this pathogen. Results Whole genome and transcriptome sequencing of the LLS fungus were obtained. A total of 233,542,110 reads of the genome were de novo assembled resulting in 1061 scaffolds, and estimated genome size 27,597,787 bp. RNA sequencing resulted in 11,848,198 reads that were de novo assembled into 13,343 contigs. Genome annotation resulted in 10,703 putative genes. BUSCO analysis of the genome and annotation resulted in 91.1% and 89.5% completeness, respectively. Phylogenetic dendrograms for 5442 bp and 4401 bp of RNA Polymerase II largest and second largest subunits, and for 5474 bp of the ribosomal RNA cistron of C. personatum are presented in relation to closely related fungi

    Blood profile holds clues to role of infection in a premonitory state for idiopathic parkinsonism and of gastrointestinal infection in established disease

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    The two-stage neuroinflammatory process, containment and progression, proposed to underlie neurodegeneration may predicate on systemic inflammation arising from the gastrointestinal tract. Helicobacter infection has been described as one switch in the pathogenic-circuitry of idiopathic parkinsonism (IP): eradication modifies disease progression and marked deterioration accompanies eradication-failure. Moreover, serum Helicobacter-antibody-profile predicts presence, severity and progression of IP. Slow gastrointestinal-transit precedes IP-diagnosis and becomes increasingly-apparent after, predisposing to small-intestinal bacterial-overgrowth (SIBO). Although IP is well-described as a systemic illness with a long prodrome, there has been no comprehensive overview of the blood profile. Here, it is examined in relation to Helicobacter status and lactulose-hydrogen-breath-testing for SIBO

    Detection of brown dwarf-like objects in the core of NGC3603

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    We use near-infrared data obtained with the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope to identify objects having the colors of brown dwarfs (BDs) in the field of the massive galactic cluster NGC 3603. These are identified through use of a combination of narrow and medium band filters spanning the J and H bands, and which are particularly sensitive to the presence of the 1.3-1.5{\mu}m H2O molecular band - unique to BDs. We provide a calibration of the relationship between effective temperature and color for both field stars and for BDs. This photometric method provides effective temperatures for BDs to an accuracy of {\pm}350K relative to spectroscopic techniques. This accuracy is shown to be not significantly affected by either stellar surface gravity or uncertainties in the interstellar extinction. We identify nine objects having effective temperature between 1700 and 2200 K, typical of BDs, observed J-band magnitudes in the range 19.5-21.5, and that are strongly clustered towards the luminous core of NGC 3603. However, if these are located at the distance of the cluster, they are far too luminous to be normal BDs. We argue that it is unlikely that these objects are either artifacts of our dataset, normal field BDs/M-type giants or extra-galactic contaminants and, therefore, might represent a new class of stars having the effective temperatures of BDs but with luminosities of more massive stars. We explore the interesting scenario in which these objects would be normal stars that have recently tidally ingested a Hot Jupiter, the remnants of which are providing a short-lived extended photosphere to the central star. In this case, we would expect them to show the signature of fast rotation.Comment: 26 Pages, 8 Figures, Accepted for publication on Ap

    Monte-Carlo Event Generators at NLO

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    A method to construct Monte-Carlo event generators at arbitrarily non-leading order is explained for the case of a non-gauge theory. A precise and correct treatment of parton kinematics is provided. Modifications of the conventional formalism are required: parton showering is not exactly the same as DGLAP evolution, and the external line prescription for the hard scattering differs from the LSZ prescription. The prospects for extending the results to QCD are discussed.Comment: 57 pages, 16 eps figures, revtex

    Comparative healthcare research outcomes of novel surgery in prostate cancer (IP4-CHRONOS): a prospective, multi-centre therapeutic phase II parallel randomised control trial

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    Introduction Focal therapy (FT) targets individual areas of cancer within the prostate, providing oncological control with minimal side-effects. Early evidence demonstrates encouraging short-medium-term outcomes. With no randomized controlled trials (RCT) comparing FT to radical therapies, Comparative Healthcare Research Outcomes of Novel Surgery in prostate cancer (CHRONOS) will compare the cancer control of these two strategies. Patients and methods CHRONOS is a parallel phase II RCT for patients with clinically significant non-metastatic prostate cancer, dependent upon clinician/patient decision, patients will enrol into either CHRONOS-A or CHRONOS-B. CHRONOS-A will randomize patients to either radical treatment or FT. CHRONOS-B is a multi-arm, multistage RCT comparing focal therapy alone to FT with neoadjuvant agents that might improve the current focal therapy outcomes. An internal pilot will determine the feasibility of, and compliance to, randomization. The proposed definitive study plans to recruit and randomize 1190 patients into CHRONOS-A and 1260 patients into CHRONOS-B. Results Primary outcome in CHRONOS-A is progression-free survival (transition to salvage local or systemic therapy, development of metastases or prostate-cancer-related mortality) and in CHRONOS-B is failure-free survival (includes the above definition and recurrence of clinically significant prostate cancer after initial FT). Secondary outcomes include adverse events, health economics and functional outcomes measured using validated questionnaires. CHRONOS is powered to assess non-inferiority of FT compared to radical therapy in CHRONOS-A, and superiority of neoadjuvant agents with FT in CHRONOS-B. Conclusion CHRONOS will assess the oncological outcomes after FT compared to radical therapy and whether neoadjuvant treatments improve cancer control following one FT session
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