313 research outputs found
Contact-allergy time
The most commonly used techniques for the in vivo evaluation of the cellular
immune response include intracutaneous testing with microbial recall antigens
or sensitization with neoantigens. The reliability of these tests for the individual
patient usually is low due to the lack of standardization and quantification.
Moreover only the efferent branch of the immune response can be judged.
The dinitrochlorobenzene-contact allergy time (DNCB-CAT) is a quantitative
approach for the assessment of the cellular immune response. 2% DNCBointment
is applied on the upper arm in a 1 cm2 area. On the following days
patch-testing with 0.05% DNCB-ointment is done on the homolateral forearm
in alternating localizations till an allergic contact dermatitis reaction appears.
As assessed in patients with malignant melanoma (MM, n=\\5) and with
lymphoproliferative disorders (LD, η = 25), the DNCB-CAT correlates with
the age of the patients and can be expressed by a formula given by the age
(years) χ factor (MM = 0.16; LD = 0.17) + constant figure (MM = 5.5;
LD = 4.3). There was no significant difference between the two groups or subgroups
investigated.
By DNCB-CAT quantitative analysis of the cellular immune response in
vivo is possible. It is an appropriate model for further investigations of the
cellular immunity under different clinical, histological, prognostic, and therapeutic
aspects
Testing common classical LTE and NLTE model atmosphere and line-formation codes for quantitative spectroscopy of early-type stars
It is generally accepted that the atmospheres of cool/lukewarm stars of
spectral types A and later are described well by LTE model atmospheres, while
the O-type stars require a detailed treatment of NLTE effects. Here model
atmosphere structures, spectral energy distributions and synthetic spectra
computed with ATLAS9/SYNTHE and TLUSTY/SYNSPEC, and results from a hybrid
method combining LTE atmospheres and NLTE line-formation with DETAIL/SURFACE
are compared. Their ability to reproduce observations for effective
temperatures between 15000 and 35000 K are verified. Strengths and weaknesses
of the different approaches are identified. Recommendations are made as to how
to improve the models in order to derive unbiased stellar parameters and
chemical abundances in future applications, with special emphasis on Gaia
science.Comment: 12 pages, 8 figures; accepted for publication in Journal of Physics:
Conference Series, GREAT-ESF Workshop: Stellar Atmospheres in the Gaia Er
Subkutane Dirofilariasis: Infektion mit Dirofilaria repens.
A female patient resident in Germany is described, who had developed dirofilariasis presenting as a hard subcutaneous nodule at the glabella. Dirofilaria repens was isolated after surgical removal of the skin lesion. She was treated with diethylcarbamazine (Hetrazan) for 4 weeks. Exposures related to infection with Dirofilaria repens are discussed
Nitrogen Enrichment in Atmospheres of A- and F- Type Supergiants
Using new accurate fundamental parameters of 30 Galactic A and F supergiants,
namely their effective temperatures Teff and surface gravities log g, we
implemented a non-LTE analysis of the nitrogen abundance in their atmospheres.
It is shown that the non-LTE corrections to the N abundances increase with
Teff. The nitrogen overabundance as a general feature of this type of stars is
confirmed. A majority of the stars has a nitrogen excess [N/Fe] between 0.2 and
0.9 dex with the maximum position of the star's distribution on [N/Fe] between
0.4 and 0.7 dex. The N excesses are discussed in light of predictions for
B-type main sequence (MS) stars with rotationally induced mixing and for their
next evolutionary phase, i.e. A- and F-type supergiants that have experienced
the first dredge-up. Rotationally induced mixing in the MS progenitors of the
supergiants may be a significant cause of the nitrogen excesses. When comparing
our results with predictions of the theory developed for stars with the mixing,
we find that the bulk of the supergiants (28 of 30) show the N enrichment that
can be expected (i) either after the MS phase for stars with the initial
rotational velocities v0 = 200-400 km s-1, (ii) or after the first dredge-up
for stars with v0 = 50-400 km s-1. The latter possibility is preferred on
account of the longer lifetime for stars on red-blue loops following the first
dredge-up. Two supergiants without a discernible N enrichment, namely HR 825
and HR 7876, may be post-MS objects with the relatively low initial rotational
velocity of about 100 km s-1. The suggested range for v0 is approximately
consistent with inferences from the observed projected rotational velocities of
B-type MS stars, progenitors of A and F supergiants.Comment: 14 pages, 13 figure
Fatal anaphylactic sting reaction in a patient with mastocytosis
We report on a 33-year-old female patient with indolent systemic mastocytosis and urticaria pigmentosa who died of an anaphylactic reaction after a yellow jacket sting. As she had no history of previous anaphylactic sting reaction, there was no testing performed in order to detect hymenoptera venom sensitization. But even if a sensitization had been diagnosed, no venom immunotherapy (VIT) would have been recommended. It is almost certain that VIT would have saved her life and it is most likely that VIT is indicated in some patients with mastocytosis with no history of anaphylactic sting reaction. However, no criteria have been established in order to allow a selection of mastocytosis patients eligible for such a `prophylactic' VIT. Copyright (C) 2008 S. Karger AG, Basel
Combined 3D characterization of porous zeolites by STEM and FIB tomography
German Research Foundation Priority Program 1570German Research Foundation Cluster of Excellence EXC 315 “Engineering of Advanced Materials
IgE-Mediated Hypersensitivity Reactions to Cannabis in Laboratory Personnel
Background: There have been sporadic reports of hypersensitivity reactions to plants of the Cannabinaceae family (hemp and hops), but it has remained unclear whether these reactions are immunologic or nonimmunologic in nature. Objective: We examined the IgE-binding and histamine-releasing properties of hashish and marijuana extracts by CAP-FEIA and a basophil histamine release test. Methods: Two workers at a forensic laboratory suffered from nasal congestion, rbinitis, sneezing and asthmatic symptoms upon occupational contact with hashish or marijuana, which they had handled frequently for 25 and 16 years, respectively. Neither patient had a history of atopic disease. Serum was analyzed for specific IgE antibodies to hashish or marijuana extract by research prototype ImmunoCAP, and histamine release from basophils upon exposure to hashish or marijuana extracts was assessed. Results were matched to those of 4 nonatopic and 10 atopic control subjects with no known history of recreational or occupational exposure to marijuana or hashish. Results: Patient 1 had specific IgE to both hashish and marijuana (CAP class 2), and patient 2 to marijuana only (CAP class 2). Controls proved negative for specific IgE except for 2 atopic individuals with CAP class 1 to marijuana and 1 other atopic individual with CAP class 1 to hashish. Stimulation of basophils with hashish or marijuana extracts elicited histamine release from basophils of both patients and 4 atopic control subjects. Conclusions: Our results suggest an IgE-related pathomechanism for hypersensitivity reactions to marijuana or hashish. Copyright (C) 2011 S. Karger AG, Base
Pristine CNO abundances from Magellanic Cloud B stars I. The LMC cluster NGC 2004 with UVES
We present chemical abundances for four main sequence B stars in the young
cluster NGC 2004 in the Large Magellanic Cloud (LMC). Apart from H II regions,
unevolved OB-type stars are currently the only accessible source of present-day
CNO abundances for the MCs not altered by stellar evolution. Using UVES on the
VLT, we obtained spectra of sufficient resolution (R = 20 000) and
signal-to-noise (S/N > 100) to derive abundances for a variety of elements (He,
C, N, O, Mg and Si) with NLTE line formation.
This study doubles the number of main sequence B stars in the LMC with
detailed chemical abundances. More importantly and in contrast to previous
studies, we find no CNO abundance anomalies brought on by e.g. binary
interaction or rotational mixing. Thus, this is the first time that abundances
from H II regions in the LMC can sensibly be cross-checked against those from B
stars by excluding evolutionary effects. We confirm the H II-region CNO
abundances to within the errors, in particular the extraordinarily low nitrogen
abundance of epsilon(N) around 7.0. Taken at face value, the nebular carbon
abundance is 0.16 dex below the B-star value which could be interpreted in
terms of interstellar dust depletion. Oxygen abundances from the two sources
agree to within 0.03 dex.
In comparison with the Galactic thin disk at MC metallicities, the Magellanic
Clouds are clearly nitrogen-poor environments.Comment: 9 pages, 4 figures, accepted by A&
Stellar spectroscopy far beyond the Local Group
Multi-object spectroscopic observations of blue supergiants in NGC 3621, a
spiral galaxy at a distance of 6.7 Mpc, carried out with the ESO VLT and FORS
are presented. We demonstrate the feasibility of quantitative stellar
spectroscopy at distances approaching a ten-fold increase over previous
investigations by determining chemical composition, stellar parameters,
reddening, extinction and wind properties of one of our targets, a supergiant
of spectral type A1 Ia located in the outskirts of NGC 3621. The metallicity
(determined from iron group elements) is reduced by a factor of two relative to
the sun in qualitative agreement with results from previous abundance studies
based on H II region oxygen emission lines. Reddening and extinction are E(B-V)
= 0.12 and Av = 0.37, respectively, mostly caused by the galactic foreground.
Comparing stellar wind momentum and absolute V magnitude with galactic and M31
counterparts we confirm the potential of the wind momentum-luminosity
relationship as an alternative tool to estimate extragalactic distances.Comment: 9 pages, 4 figures, 1 table, accepted for publication in The
Astrophysical Journal Letter
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