78 research outputs found
Cytokine status disorders in children with urticaria
Objective: to study the state of cytokine status in children with acute and chronic urticaria.Materials and methods: 264 children of both sexes aged from 6 to 16 years with different variants of urticaria were examined. Clinical research methods included analysis of anamnestic data, objective examination of the child to determine the severity of urticaria. Immunological research methods included determination of IL-4, IL-6, IL-17, and IFN-γ levels by the method of enzyme immunoassay of blood serum.Results: cytokine profile analysis revealed hyperproduction of IL-17, γ-IFN with reduced IL-4 synthesis in children with acute urticaria. In children with chronic urticaria, IL-6 hyperproduction is noted against the background of a significant decrease in IL-4 synthesis.Conclusion: there was a significant relationship between the development of severe acute urticaria and the levels of proinflammatory cytokines IL-6, IL-17, and between the formation of chronic urticaria and the level of IL-6
Morphological verification of the first missed abortion
Objective. The study aimed to compare the level of INF a2 immunoexpression in tissues obtained during medical abortion with the corresponding level of IFNa2 expression in a retained fetal egg tissues after the first missed abortion. The authors compared the anamnestic data on previous inflammatory diseases of the genital tract with the results of an extended morphological study of the material obtained during the evacuation of the contents of the uterine cavity during the first non-developing pregnancy in the first trimester.Materials and methods. The study included 15 patients with first-time missed abortions caused by a viral infection (6-8 weeks of pregnancy). All patients demonstrated either recurrent herpes simplex labialis/genitalis or PCR confirmed HSV, HPV, CMV. Exclusion criteria were recurrent miscarriage, blighted ovum, endocrinopathies, male factor infertility, and other causes of miscarriage. The comparison group included 20 women of the same age that chose to undergo a medical abortion.Results. In patients from the comparison group, the main producer of IFN a2 was syncytiotrophoblast as well as maternal decidual cells in the parietal endometrium and uteroplacental area. In the main group, manifested hematogenous infection (microabscesses, vasculitis, lymphocytic and macrophage infiltration) with dystrophy and necrosis of decidual maternal cells and secondary pathological changes in the placental villi were diagnosed, which led to a significant decrease in the IFN a2 immunoexpression in all the studied cells.Conclusion. The lack of anamnestic data on previous urogenital infections does not exclude the etiological role of the inflammatory component in the genesis of non-developing pregnancy. First-time occurred pregnancy loss requires adequate postoperative interferon therapy and a thorough examination of a couple
A case of timely diagnosis and successful surgical correction of the left pulmonary artery sling in a newborn
The article describes a clinical observation of a newborn patient with a rare congenital cardiovascular disorder of the left pulmonary artery sling. There are few publications in the world’s literature on the clinical observations of the above pathology, which causes the key difficulty in diagnostics. Moreover, this case features a favorable outcome thanks to a timely diagnosis and a successful surgical correction that followed
Single electron emission in two-phase xenon with application to the detection of coherent neutrino-nucleus scattering
We present an experimental study of single electron emission in ZEPLIN-III, a
two-phase xenon experiment built to search for dark matter WIMPs, and discuss
applications enabled by the excellent signal-to-noise ratio achieved in
detecting this signature. Firstly, we demonstrate a practical method for
precise measurement of the free electron lifetime in liquid xenon during normal
operation of these detectors. Then, using a realistic detector response model
and backgrounds, we assess the feasibility of deploying such an instrument for
measuring coherent neutrino-nucleus elastic scattering using the ionisation
channel in the few-electron regime. We conclude that it should be possible to
measure this elusive neutrino signature above an ionisation threshold of
3 electrons both at a stopped pion source and at a nuclear reactor.
Detectable signal rates are larger in the reactor case, but the triggered
measurement and harder recoil energy spectrum afforded by the accelerator
source enable lower overall background and fiducialisation of the active
volume
Quenching Factor for Low Energy Nuclear Recoils in a Plastic Scintillator
Plastic scintillators are widely used in industry, medicine and scientific
research, including nuclear and particle physics. Although one of their most
common applications is in neutron detection, experimental data on their
response to low-energy nuclear recoils are scarce. Here, the relative
scintillation efficiency for neutron-induced nuclear recoils in a
polystyrene-based plastic scintillator (UPS-923A) is presented, exploring
recoil energies between 125 keV and 850 keV. Monte Carlo simulations,
incorporating light collection efficiency and energy resolution effects, are
used to generate neutron scattering spectra which are matched to observed
distributions of scintillation signals to parameterise the energy-dependent
quenching factor. At energies above 300 keV the dependence is reasonably
described using the semi-empirical formulation of Birks and a kB factor of
(0.014+/-0.002) g/MeVcm^2 has been determined. Below that energy the measured
quenching factor falls more steeply than predicted by the Birks formalism.Comment: 8 pages, 9 figure
WIMP-nucleon cross-section results from the second science run of ZEPLIN-III
We report experimental upper limits on WIMP-nucleon elastic scattering cross
sections from the second science run of ZEPLIN-III at the Boulby Underground
Laboratory. A raw fiducial exposure of 1,344 kg.days was accrued over 319 days
of continuous operation between June 2010 and May 2011. A total of eight events
was observed in the signal acceptance region in the nuclear recoil energy range
7-29 keV, which is compatible with background expectations. This allows the
exclusion of the scalar cross-section above 4.8E-8 pb near 50 GeV/c^2 WIMP mass
with 90% confidence. Combined with data from the first run, this result
improves to 3.9E-8 pb. The corresponding WIMP-neutron spin-dependent
cross-section limit is 8.0E-3 pb. The ZEPLIN programme reaches thus its
conclusion at Boulby, having deployed and exploited successfully three liquid
xenon experiments of increasing reach
Results from the First Science Run of the ZEPLIN-III Dark Matter Search Experiment
The ZEPLIN-III experiment in the Palmer Underground Laboratory at Boulby uses
a 12kg two-phase xenon time projection chamber to search for the weakly
interacting massive particles (WIMPs) that may account for the dark matter of
our Galaxy. The detector measures both scintillation and ionisation produced by
radiation interacting in the liquid to differentiate between the nuclear
recoils expected from WIMPs and the electron recoil background signals down to
~10keV nuclear recoil energy. An analysis of 847kg.days of data acquired
between February 27th 2008 and May 20th 2008 has excluded a WIMP-nucleon
elastic scattering spin-independent cross-section above 8.1x10(-8)pb at
55GeV/c2 with a 90% confidence limit. It has also demonstrated that the
two-phase xenon technique is capable of better discrimination between electron
and nuclear recoils at low-energy than previously achieved by other xenon-based
experiments.Comment: 12 pages, 17 figure
A case of hyperplasia of the adrenal cortex in the newborn child
Clinical observation of a hyperplasia of the adrenal cortex in the newborn is presented. Main feature of this observation is the complicated course of this disease in the newborn against hypoxemic defeat of the central nervous system and neonatal jaundice. Now treatment of this congenital disease has to begin with the first week of life and includes complete hormonal and infusion therapy. In this observation child’s clinical improvement is noted
The Tevatron at the Frontier of Dark Matter Direct Detection
Direct detection of dark matter (DM) requires an interaction of dark matter
particles with nucleons. The same interaction can lead to dark matter pair
production at a hadron collider, and with the addition of initial state
radiation this may lead to mono-jet signals. Mono-jet searches at the Tevatron
can thus place limits on DM direct detection rates. We study these bounds both
in the case where there is a contact interaction between DM and the standard
model and where there is a mediator kinematically accessible at the Tevatron.
We find that in many cases the Tevatron provides the current best limit,
particularly for light dark matter, below 5 GeV, and for spin dependent
interactions. Non-standard dark matter candidates are also constrained. The
introduction of a light mediator significantly weakens the collider bound. A
direct detection discovery that is in apparent conflict with mono-jet limits
will thus point to a new light state coupling the standard model to the dark
sector. Mono-jet searches with more luminosity and including the spectrum shape
in the analysis can improve the constraints on DM-nucleon scattering cross
section.Comment: 20 pages, 8 figures, final version in JHE
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