89 research outputs found
Study on the Epidemiology and Clinical Picture of Human Parainfluenza Virus in Chennai. Standardization of Rapid Diagnostic Tool and to Study the Effect of Hemagglutinin Neuraminidase Inhibitors on the Isolates
Human parainfluenza viruses are a group of viruses that cause different types of respiratory infections and are most common in children and infants.
Throat and nasal swabs were collected from symptomatic patients in Chennai within three days onset of illness were determined the prevalence of HPIV by Multiplex reverse transcription PCR. Epidemiology of specific viral etiology in patients was observed throughout the years. The age wise distribution of HPIV cases were analyzed and divided into 0-10, 11-20, 21-30, 31-40, 41-50 and above 50. The prevalence in different age groups was statistically analyzed by standard error mean. Their positivity was observed in all the years during monsoon months of August to September and post monsoon months of November to February. Among the four serotypes HPIV type 3 is highly predominant in all the years (2011-2014). HPIV-2 positivity were occurred rarely in 2014. This study validates the prevalence of HPIV infection in Chennai and indicates the circulating serotypes and HPIV strains.
The PCR products were sequenced and submitted to genbank and assigned the accession number. Different sequences were retrieved from NCBI and aligned as FASTA format. Mutations were identified by multiple sequence alignment of HPIV by ClustalW tool. Amino acid alterations were identified in HPIV-3 (HN gene) at residue 295 which Histidine replaced by Tyrosine and at 297 which Serine replaced by Glycine. Another mutations were identified in HPIV-2 (N gene) at residue 138 which Histidine replaced by Tyrosine and at 140th residue identified amino acid alteration which Histidine replaced by Glutamine. The phylogenetic analysis were identified the homology of Chennai strains with other strains. HPIV type 3 (HN) strain was clustered with Fukuoka /2009, Nagasaki 2009 and Wash 64979. HPIV type 3 (NP) strain was grouped with Switzerland/2013, US/2000, and South Africa/2000. HPIV type 2 was compared with Greer strain and HPIV2/V94.
All clinical samples were cultured in the LLC-MK2, A549 and MDCK cell lines. Then specificity and sensitivity of the cell passages were characterized for clinical isolates. The number of positive cases were highly significant in the year 2011 followed by 2013. Out of 931 samples, 38 were isolated by LLC-MK2, 15 samples identified CPE in A549 and only 5 samples were grew in MDCK cells. Among the three cell lines LLC-MK2 was highly predominant for the isolation of
HPIV. Positive percentage remained very small in MDCK cell line thus for further confirmation were not studied, whereas other two cell lines LLC-MK2 and A549 performed further confirmation. The isolated Human parainfluenza virus type 2 were more sensitive in the early passages of 8 and 9 at day five for LLC-MK2, highly compatible in the 5th passage at day 7 for A549 and 8th passage at day 8 for MDCK passage at day 8 for rest of the passages were less sensitive and specificity. HPIV-3 was more accustomed in the 9th passage at day 5 for LLC-MK2.
The virus isolated samples were performed by hemadsorption assay (HAD) was aimed at confirmation of cytopathic effect were identified in LLC-MK2, A549 cell lines. Among the two cell lines LLC-MK2 was highly predominant to detect erythrocytes adhered on the monolayers and followed A549 cell lines. Cells infected with HPIV with C.Perfringens treatment by HAD assay to enhance erythrocyte binding for HPIV-2 (82%) and HPIV-3 (90%) in 24 well plate. Virus isolated samples were confirmed by plaque assay. Plaque was observed after 8-10 days of
incubation. Interactions of receptors between HPIV-2 and 3 with m.o.i. in LLC-MK2 appeared as fusion were not blocked in HPIV-2 whereas HPIV-3 achieved fusion were blocked syncytium was not formed. Similar outcomes remained in A549 cells. Further the study evaluated the neuraminidase enzyme activity of HPIV. 4-MU concentrations and used determined the percentage of substrate expended during the reaction. The signal to background ratio were determined as the fluorescence intensities restrained after 20 minutes. The substrate concentrations were used at 25 μM. Various concentration of HPIV- 2 and 3 (m.o.i.) with bacterial neuraminidase were performed by neuraminidase activity which are statistically significant.
Cytotoxicity of 4-GU-DANA at the concentrations less than 400 μM in A549 and greater than 641 μM in LLC-MK2 by MTT assay. Cytotoxicity of Ribavirin at the concentrations less than 405 μM in A549 and greater than 476 μM in LLC-MK2 by MTT assay. Cytotoxic percentage of Ribavirin were appears as high when compared with HN inhibitor. Cytotoxicity of glycyrrhizic acid form
Licorice at concentration 31 μM in LLC-MK2 and 45 μM in A549 were identified. Indicates that MTT obtained better results compared with other dyes.
Antiviral activity of neuraminidase inhibitor (4-GU-DANA) against HPIV by Hemadsorption inhibition assay was performed and ability to interfere with receptor interaction of HPIV-2 and 3 blocks hemadsorption activity at 600 μM seemed as 77% and 78% respectively. 4-GU-DANA inhibits receptor binding for HPIV-2 and 3 at 500 µM (60%) inhibit plaque formation in LL-CMK2 and (67%) and (79%) inhibit plaque reduction in A549 cells. In neuraminidase inhibition assay, less concentrations which inhibit the HPIV-2 and 3. The IC50 concentration for HPIV-2 at 2.5 μM and HPIV-3 at 1.6 μM. 4-GU-DANA concentrations were obtained less deliberation for HPIV-3 when compared to HPIV-2.
Antiviral activity of nucleoside inhibitor (Ribavirin) against HPIV type 2 and 3 by hemadsorption inhibition assay was performed to inhibit the adherence of erythrocytes to the monolayer of HPIV type 2 and 3 at 400 μM (77%) and (75%) individually. Ribavirin inhibits replication for HPIV-2 and 3 at 400 μM during pre and post adsorption period in LLC-MK2 and A549 cells. There was no significant reduction in plaque number due to existence of ribavirin during the adsorption period of 90 minutes. The plaque area was reduced by addition after the adsorption period. Further confirmed inhibition of HPIV-2 by molecular characterized, observed infected cells without drug showed band by molecular characteristics. RBV treated infected cells, band cannot be seen and indicating that RBV inhibited transcription of viral genome.
Cytotoxicity of Glycyrrihic acid from Licorice generated at 31 μM for LLC-MK2 and 45 μM for A549 by MTT assay. Antiviral activity of Glycyrrihic acid against HPIV-2 and 3 by hemadsorption inhibition assay was achieved to inhibit the erythrocyte adherence to the monolayer of HPIV-2 and 3 at 100 μM inhibition percentage was occurred 90% and 95% respectively. Glycyrrihic acid compound inhibits plaque formation at 70 μM replication of viral growth percentage was 86% for LLC-MK2 and 87% for A549 cells. Further confirmed by neuraminidase inhibition assay were performed at less concentration for HPIV-2 and 3 at 1.5 μM and 1.2 μM respectively.
Neuraminidase inhibitor (Zanamivir) and nucleoside inhibitor (Ribavirin) were performed for antiviral activity against HPIV-2 and 3. Among these inhibitors Ribavirin has highly preferable with less concentration when compared to HN inhibitor. Among these three compounds natural glycyrrhizic acid from Licorice root were performed and observed very minimum concentration to inhibit both serotype of Human parainfluenza virus-2 and 3. The following inhibitors namely
Neuraminidase inhibitor (Zanamivir) and nucleoside inhibitors (Ribavirin) maximum concentration was used to inhibit the HPIV-2 and 3. Finally, the phytal compound glycyrrhizic acid from licorice showed comparatively high inhibition on the viral growth in invitro screening. The Zanamivir nucleoside analog was elucidated for the mechanism of antiviral activity. The HN receptor of HPIV was docked with ligand Zanamivir using Autodock programme. All the HN receptor was significantly docked by Zanamivir. The 1V2i receptor was prominently docked with (95%) high frequency and good dock score
Random sampling of an AC source: A tool to teach probabilistic observations
An undergraduate level experiment is described to demonstrate the role of
probabilistic observations in physics. A capacitor and a DC voltmeter are used
to randomly sample an AC voltage source. The resulting probability distribution
is analyzed to extract information about the AC source. Different
characteristic probability distributions arising from various AC waveforms are
calculated and experimentally measured. The reconstruction of the AC waveform
is demonstrated from the measured probability distribution under certain
restricted circumstances. The results are also compared with a simulated data
sample. We propose this as a pedagogical tool to teach probabilistic
measurements and their manipulations.Comment: Revtex4 file, 10 pages with 8 figure
QCD Working Group Report
This is the report of the QCD working group at WHEPP 6. Discussions and work
on heavy ion collisions, polarised scattering, and collider phenomenology are
reported.Comment: Report of the QCD group at WHEPP-6, Chennai, January 2000. 7 page
Phenomenology of single spin asymmetries in p(transv. polarized)-p -> pion + X
A phenomenological description of single transverse spin effects in
hadron-hadron inclusive processes is proposed, assuming a generalized
factorization scheme and pQCD hard interactions. The transverse momentum, k_T,
of the quarks inside the hadrons and of the hadrons relatively to the
fragmenting quark, is taken into account in distribution and fragmentation
functions, and leads to possible non zero single spin asymmetries. The role of
k_T and spin dependent quark fragmentations -- the so-called Collins effect --
is investigated in details in p(transv. polarized)-p -> pion + X processes: it
is shown how the experimental data could be described, obtaining an explicit
expression for the spin asymmetry of a polarized fragmenting quark, on which
some comments are made. Predictions for other processes, possible further
applications and experimental tests are discussed.Comment: 20+1 pages, LaTeX, 6 eps figures, uses epsfig.sty. Version v2: Some
sentences rephrased and comments added throughout the paper; one reference
added; no changes in results and figures. Final version to be published in
Phys. Rev.
J/\psi production through resolved photon processes at e+ e- colliders
We consider J/psi photoproduction in e+ e- as well as linear photon
colliders. We find that the process is dominated by the resolved photon
channel. Both the once-resolved and twice-resolved cross-sections are sensitive
to (different combinations of) the colour octet matrix elements. Hence, this
may be a good testing ground for colour octet contributions in NRQCD. On the
other hand, the once-resolved J/psi production cross-section, particularly in a
linear photon collider, is sensitive to the gluon content of the photon. Hence
these cross-sections can be used to determine the parton distribution
functions, especially the gluon distribution, in a photon, if the colour octet
matrix elements are known.Comment: Added a figure on parametrisation dependence of photonic parton
densities and some reference
Statistical approach for unpolarized fragmentation functions for the octet baryons
A statistical model for the parton distributions in the nucleon has proven
its efficiency in the analysis of deep inelastic scattering data, so we propose
to extend this approach to the description of unpolarized fragmentation
functions for the octet baryons. The characteristics of the model are
determined by using some data on the inclusive production of proton and
in unpolarized deep inelastic scattering and a next-to-leading
analysis of the available experimental data on the production of unpolarized
octet baryons in annihilation. Our results show that both parton
distributions and fragmentation functions are compatible with the statistical
approach, in terms of a few free parameters, whose interpretation will be
discussed.Comment: 14 pages, 7 eps figures, to appear in Phys. Rev.
Precision on leptonic mixing parameters at future neutrino oscillation experiments
We perform a comparison of the different future neutrino oscillation
experiments based on the achievable precision in the determination of the
fundamental parameters theta_{13} and the CP phase, delta, assuming that
theta_{13} is in the range indicated by the recent Daya Bay measurement. We
study the non-trivial dependence of the error on delta on its true value. When
matter effects are small, the largest error is found at the points where CP
violation is maximal, and the smallest at the CP conserving points. The
situation is different when matter effects are sizable. As a result of this
effect, the comparison of the physics reach of different experiments on the
basis of the CP discovery potential, as usually done, can be misleading. We
have compared various proposed super-beam, beta-beam and neutrino factory
setups on the basis of the relative precision of theta_{13} and the error on
delta. Neutrino factories, both high-energy or low-energy, outperform
alternative beam technologies. An ultimate precision on theta_{13} below 3% and
an error on delta of < 7^{\circ} at 1 sigma (1 d.o.f.) can be obtained at a
neutrino factory.Comment: Minor changes, matches version accepted in JHEP. 30 pages, 9 figure
Supersymmetric Origin of Neutrino Mass
Supersymmetry with breaking of R-parity provides an attractive way to
generate neutrino masses and lepton mixing angles in accordance to present
neutrino data. We review the main theoretical features of the bilinear R-parity
breaking (BRpV) model, and stress that it is the simplest extension of the
minimal supersymmetric standard model (MSSM) which includes lepton number
violation. We describe how it leads to a successful phenomenological model with
hierarchical neutrino masses. In contrast to seesaw models, the BRpV model can
be probed at future collider experiments, like the Large Hadron Collider or the
Next Linear Collider, since the decay pattern of the lightest supersymmetric
particle provides a direct connection with the lepton mixing angles determined
by neutrino experiments.Comment: 21 pages, 8 figures, review for NJP focus issue on neutrino
Interim Design Report
The International Design Study for the Neutrino Factory (the IDS-NF) was
established by the community at the ninth "International Workshop on Neutrino
Factories, super-beams, and beta- beams" which was held in Okayama in August
2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for
the facility on the timescale of 2012/13. In addition, the mandate for the
study [3] requires an Interim Design Report to be delivered midway through the
project as a step on the way to the RDR. This document, the IDR, has two
functions: it marks the point in the IDS-NF at which the emphasis turns to the
engineering studies required to deliver the RDR and it documents baseline
concepts for the accelerator complex, the neutrino detectors, and the
instrumentation systems. The IDS-NF is, in essence, a site-independent study.
Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific
issues to be addressed in the cost analysis that will be presented in the RDR.
The choice of example sites should not be interpreted as implying a preferred
choice of site for the facility
Neutrinos from Stellar Collapse: Effects of flavour mixing
We study the effect of non-vanishing masses and mixings among neutrino
flavours on the detection of neutrinos from stellar collapse by a water
Cerenkov detector. We consider a realistic framework in which there are three
neutrino flavours whose mass squared differences and mixings are constrained by
the present understanding of solar and atmospheric neutrinos. We also include
the effects of high dense matter within the supernova core. We find that the
number of events due to the dominant process involving electron-antineutrinos
may change dramatically for some allowed mixing parameters. Furthermore,
contributions from charged-current scattering off oxygen atoms in the detector
can be considerably enhanced due to flavour mixing; such events have a distinct
experimental signature since they are backward-peaked. Hence, mixing has a
non-trivial effect on the signature of neutrinos (and antineutrinos) from
stellar collapse.Comment: 22 pages Latex file, with 6 postscript figures, minor changes made in
tex
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