1,602 research outputs found

    APRIL:TACI axis is dispensable for the immune response to rabies vaccination.

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    There is significant need to develop a single-dose rabies vaccine to replace the current multi-dose rabies vaccine regimen and eliminate the requirement for rabies immune globulin in post-exposure settings. To accomplish this goal, rabies virus (RABV)-based vaccines must rapidly activate B cells to secrete antibodies which neutralize pathogenic RABV before it enters the CNS. Increased understanding of how B cells effectively respond to RABV-based vaccines may improve efforts to simplify post-exposure prophylaxis (PEP) regimens. Several studies have successfully employed the TNF family cytokine a proliferation-inducing ligand (APRIL) as a vaccine adjuvant. APRIL binds to the receptors TACI and B cell maturation antigen (BCMA)-expressed by B cells in various stages of maturation-with high affinity. We discovered that RABV-infected primary murine B cells upregulate APRIL ex vivo. Cytokines present at the time of antigen exposure affect the outcome of vaccination by influencing T and B cell activation and GC formation. Therefore, we hypothesized that the presence of APRIL at the time of RABV-based vaccine antigen exposure would support the generation of protective antibodies against RABV glycoprotein (G). In an effort to improve the response to RABV vaccination, we constructed and characterized a live recombinant RABV-based vaccine vector which expresses murine APRIL (rRABV-APRIL). Immunogenicity testing in mice demonstrated that expressing APRIL from the RABV genome does not impact the primary antibody response against RABV G compared to RABV alone. In order to evaluate the necessity of APRIL for the response to rabies vaccination, we compared the responses of APRIL-deficient and wild-type mice to immunization with rRABV. APRIL deficiency does not affect the primary antibody response to vaccination. Furthermore, APRIL expression by the vaccine did not improve the generation of long-lived antibody-secreting plasma cells (PCs) as serum antibody levels were equivalent in response to rRABV-APRIL and the vector eight weeks after immunization. Moreover, APRIL is dispensable for the long-lived antibody-secreting PC response to rRABV vaccination as anti-RABV G IgG levels were similar in APRIL-deficient and wild-type mice six months after vaccination. Mice lacking the APRIL receptor TACI demonstrated primary anti-RABV G antibody responses similar to wild-type mice following immunization with the vaccine vector indicating that this response is independent of TACI-mediated signals. Collectively, our findings demonstrate that APRIL and associated TACI signaling is dispensable for the immune response to RABV-based vaccination

    DEVELOPMENT AND VALIDATION OF UV SPECTROPHOTOMETRIC METHOD AND RP-HPLC METHOD FOR ESTIMATION OF CAPECITABINE IN BULK AND TABLET DOSAGE FORMS

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    Objective: The objective of the present work is to develop and validate a novel, specific, precise and reliable method for estimation of Capecitabine in bulk and pharmaceutical dosage form using UV-visible spectroscopy and RP-HPLC method. Methods: UV-visible spectrophotometric determination was performed with Elico double beam SL 210 UV-visible spectrophotometer having deuterium lamp at λmax 304 nm using water as a medium. Linearity was noted over a concentration range of 2-20 µg/ml with a correlation coefficient of 0.99. HPLC analysis was performed using Eclipse XDB C18 column with 5 µm particle size having dimensions 4.6 X 250 mm column, Agilent 1260 infinity DAD detector, 1260 infinity quaternary pump using Ezchrome software at a flow rate of 1 ml/min and a run time pressure of 2140 psi. Methanol: acetonitrile: water in the ratio 30: 30: 40 was used as mobile phase and the effluents were analyzed at 304 nm. Both the proposed methods were validated for various parameters like linearity, precision, accuracy, robustness, ruggedness, selectivity, detection, quantification limits, formulation analysis as per International Conference on Harmonization (ICH) guidelines. Results: Linearity for UV and HPLC method was noted over a concentration range of 2-100 µg/ml with a correlation coefficient of 0.99. The retention time was considered to be 4.60 min. The % RSD for interday and intraday precision studies and recovery analysis of both UV and HPLC methods was found to be less than 1% which is less than the official RSD limit (2%). Recovery analysis performed using marketed formulation capeguard was considered to be greater than 99% for both the methods. Conclusion: Both the methods developed were validated according to the ICH guidelines. Hence it was evident that the developed methods were novel, sensitive, precise and reliable for estimation of Capecitabine in bulk and were successfully applied for estimation of pharmaceutical dosage forms. Keywords: Capecitabine, UV-visible spectroscopic method, HPLC method, Validatio

    Tensile and Wear Behavior of Calotropis Gigentea Fruit Fiber Reinforced Polyester Composites

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    AbstractAn experimental study has been carried out to investigate the tensile and wear characterization of polymer composites made by reinforcing Calotropis Gigentea fruit fiber as a new natural fiber into a polyester resin. The Calotropis Gigentea fibres extracted by manual processes have been used to fabricate the composites. The composites are fabricated up to a maximum volume fraction of fibre of 0.35. The tensile strength increased with increase in fiber content. Further, the wear behavior of the Calotropis Gigentea fruit fiber composite were studied with increase in fiber content

    Subwavelength atom localization via amplitude and phase control of the absorption spectrum

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    We propose a scheme for subwavelength localization of an atom conditioned upon the absorption of a weak probe field at a particular frequency. Manipulating atom-field interaction on a certain transition by applying drive fields on nearby coupled transitions leads to interesting effects in the absorption spectrum of the weak probe field. We exploit this fact and employ a four-level system with three driving fields and a weak probe field, where one of the drive fields is a standing-wave field of a cavity. We show that the position of an atom along this standing wave is determined when probe field absorption is measured. We find that absorption of the weak probe field at a certain frequency leads to subwavelength localization of the atom in either of the two half-wavelength regions of the cavity field by appropriate choice of the system parameters. We term this result as sub-half-wavelength localization to contrast it with the usual atom localization result of four peaks spread over one wavelength of the standing wave. We observe two localization peaks in either of the two half-wavelength regions along the cavity axis.Comment: Accepted for publication to Physical Review

    A NOVEL MATLAB/SIMELECTRONICS MODEL OF PV ARRAY WITH MPPT CONTROLLER

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    A photovoltaic array (PVA) simulation model to be used in Matlab-Simelectronic GUI environment will be developed and analyzed in this paper. In Simelectronic environment the simulink signal is converted to physical signal and again physical signal is converted to simulink signal. The model is developed using basic circuit equations of the photovoltaic (PV) solar cells including the effects of solar irradiation and temperature changes. The new model developed will be tested using a directly coupled dc load. A new implemented Photovoltaic Array Simulation model is to be developed by using Matlab/ Simelectronic Simulation Software. Test and validation studies with proper load matching circuits are simulated and results are presented here

    Hepatocyte Growth Factor Receptor c-Met Instructs T Cell Cardiotropism and Promotes T Cell Migration to the Heart via Autocrine Chemokine Release

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    © 2015 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)This study was funded by the British Heart Foundation (RG/09/002/2642 to F.M.M.-B.) and the Medical Research Council of the UK (G0901084 to F.M.M.-B.). ImageStream X was funded by the Wellcome Trust (101604/Z/13/Z). This work forms part of the research themes contributing to the translational research portfolio of Barts and the London Cardiovascular Biomedical Research Unit, which is supported and funded by the National Institute of Health Research

    Landings of Giant Manta Rays at Cochin Fisheries Harbour

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    Three numbers of Giant Manta ray, Manta birostris locally known as “Aana Thirandi” measuring 220, 291 and 285 cm in standard length and weighing 680, 1080 and 1050 kg respectively were landed at Cochin Fisheries Harbour on 27th March, 2015 (Fig.1). The rays though landed by deep sea trawler, were caught by mechanized gill net boat operated at depth of 200 m off Kochi. Due to the big size of the rays caught, the gill net fishermen had transferred them to a deep sea trawler which operated nearby

    Thioridazine: a potential adjuvant in pharmacotherapy of drug resistant tuberculosis Ki

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    Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis. Despite advances in control strategies, inadequate treatment and failure to comply with drug regimens have resulted in TB to emerge as one of the most common and deadly infectious diseases worldwide. The emergence of drug-resistant TBhas evolved as a formidable obstacle for comprehensive TB control. Drug-resistant TB can be classified as multi-drug-resistant TB, extensively drug-resistant TB and totally drug resistant TB (TDR-TB). There is a paucity in the development of new drugs against drug-resistant mycobacteria. The focus has shifted to the exploration of anti-mycobacterial properties of drugs approved for other indications. Thioridazine, a drug approved for use in schizophrenia is one such potential agent, which has shown anti-mycobacterial activity. There is evidence of anti-mycobacterial action of Thioridazine in in-vitro and mouse models. There is a compelling need for new anti-mycobacterial drugs that are more effective and have less toxicity. Further clinical trials are advocated favoring the use of thioridazine as an adjuvant in the treatment of TB, especially TDR-TB

    Effects of the Nearest-Neighbour Coulomb Interactions on the Ground State of the Periodic Anderson Model

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    The magnetic and non-magnetic ground states of the periodic Anderson model with Coulomb interaction between ff-electrons on the nearest-neighbour(NN) sites are investigated using a variational method, which gives exact calculation of the expectation values in the limit of infinite dimensions. It is shown that for a critical value of NN Coulomb interactions the magnetic ground state of the periodic Anderson model in the Kondo regime is unstable. Factors in terms of the physical processes responsible for instability of the magnetic ground state are also discussed. Our study indicates the importance of the NN Coulomb interactions for correlated two band models.Comment: RevTeX, 6 pages, 5 figures, to appear in Phys. Rev.
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