88 research outputs found
Suppression of Lymphoma and Epithelial Malignancies Effected by Interferon γ
The immunosurveillance of transformed cells by the immune system remains one of the most controversial and poorly understood areas of immunity. Gene-targeted mice have greatly aided our understanding of the key effector molecules in tumor immunity. Herein, we describe spontaneous tumor development in gene-targeted mice lacking interferon (IFN)-γ and/or perforin (pfp), or the immunoregulatory cytokines, interleukin (IL)-12, IL-18, and tumor necrosis factor (TNF). Both IFN-γ and pfp were critical for suppression of lymphomagenesis, however the level of protection afforded by IFN-γ was strain specific. Lymphomas arising in IFN-γ-deficient mice were very nonimmunogenic compared with those derived from pfp-deficient mice, suggesting a comparatively weaker immunoselection pressure by IFN-γ. Single loss of IL-12, IL-18, or TNF was not sufficient for spontaneous tumor development. A significant incidence of late onset adenocarcinoma observed in both IFN-γ– and pfp-deficient mice indicated that some epithelial tissues were also subject to immunosurveillance
Current clinical practice in disabling and chronic migraine in the primary care setting: results from the European My-LIFE anamnesis survey.
Migraine is a prevalent and disabling headache disorder that affects more than 1.04 billion individuals world-wide. It can result in reduction in quality of life, increased disability, and high socio-economic burden. Nevertheless, and despite the availability of evidence-based national and international guidelines, the management of migraine patients often remains suboptimal, especially for chronic migraine (CM) patients.
My-LIFE anamnesis project surveyed 201 General practitioners (GPs) from 5 European countries (France, Germany, Italy, Spain, and the UK) with the aim of understanding chronic migraine (CM) patients' management in the primary care setting.
In our survey, GPs diagnosed episodic migraine (EM) more often than CM (87% vs 61%, p < 0.001). We found that many CM patients were not properly managed or referred to specialists, in contrast to guidelines recommendations. The main tools used by primary-care physicians included clinical interview, anamnesis guide, and patient diary. Tools used at the first visit differed from those used at follow-up visits. Up to 82% of GPs reported being responsible for management of patients diagnosed with disabling or CM and did not refer them to a specialist. Even when the GP had reported referring CM patients to a specialist, 97% of them were responsible for their follow-up. Moreover, the treatment prescribed, both acute and preventive, was not in accordance with local and international recommendations. GPs reported that they evaluated the efficacy of the treatment prescribed mainly through patient perception, and the frequency of follow-up visits was not clearly established in the primary care setting. These results suggest that CM is underdiagnosed and undertreated; thereby its management is suboptimal in the primary care.
There is a need of guidance in the primary care setting to both leverage the management of CM patients and earlier referral to specialists, when appropriate
On the compatibility of a flux transport dynamo with a fast tachocline scenario
The compatibility of the fast tachocline scenario with a flux transport
dynamo model is explored. We employ a flux transport dynamo model coupled with
simple feedback formulae relating the thickness of the tachocline to the
amplitude of the magnetic field or to the Maxwell stress. The dynamo model is
found to be robust against the nonlinearity introduced by this simplified fast
tachocline mechanism. Solar-like butterfly diagrams are found to persist and,
even without any parameter fitting, the overall thickness of the tachocline is
well within the range admitted by helioseismic constraints. In the most
realistic case of a time and latitude dependent tachocline thickness linked to
the value of the Maxwell stress, both the thickness and its latitude dependence
are in excellent agreement with seismic results. In the nonparametric models,
cycle related temporal variations in tachocline thickness are somewhat larger
than admitted by helioseismic constraints; we find, however, that introducing a
further parameter into our feedback formula readily allows further fine tuning
of the thickness variations.Comment: Accepted in Solar Physic
Reflection and Ducting of Gravity Waves Inside the Sun
Internal gravity waves excited by overshoot at the bottom of the convection
zone can be influenced by rotation and by the strong toroidal magnetic field
that is likely to be present in the solar tachocline. Using a simple Cartesian
model, we show how waves with a vertical component of propagation can be
reflected when traveling through a layer containing a horizontal magnetic field
with a strength that varies with depth. This interaction can prevent a portion
of the downward-traveling wave energy flux from reaching the deep solar
interior. If a highly reflecting magnetized layer is located some distance
below the convection zone base, a duct or wave guide can be set up, wherein
vertical propagation is restricted by successive reflections at the upper and
lower boundaries. The presence of both upward- and downward-traveling
disturbances inside the duct leads to the existence of a set of horizontally
propagating modes that have significantly enhanced amplitudes. We point out
that the helical structure of these waves makes them capable of generating an
alpha-effect, and briefly consider the possibility that propagation in a shear
of sufficient strength could lead to instability, the result of wave growth due
to over-reflection.Comment: 23 pages, 5 figures. Accepted for publication in Solar Physic
Data from: Multi-modal signal evolution in birds: re-examining a standard proxy for sexual selection
Sexual selection is proposed to be an important driver of speciation and phenotypic diversification in animal systems. However, previous phylogenetic tests have produced conflicting results, perhaps because they have focused on a single signalling modality (visual ornaments), whereas sexual selection may act on alternative signalling modalities (e.g. acoustic ornaments). Here we compile phenotypic data from 259 avian sister species pairs to assess the relationship between visible plumage dichromatism—a standard index of sexual selection in birds—and macroevolutionary divergence in the other major avian signalling modality: song. We find evidence for a strong negative relationship between the degree of plumage dichromatism and divergence in song traits, which remains significant even when accounting for other key factors, including habitat type, ecological divergence and interspecific interactions. This negative relationship is opposite to the pattern expected by a straightforward interpretation of the sexual selection-diversification hypothesis, whereby higher levels of dichromatism indicating strong sexual selection should be related to greater levels of mating signal divergence regardless of signalling modality. Our findings imply a ‘trade-off’ between the elaboration of visual ornaments and the diversification of acoustic mating signals, and suggest that the effects of sexual selection on diversification can only be determined by considering multiple alternative signalling modalities
Data from: Multi-modal signal evolution in birds: re-examining a standard proxy for sexual selection
Sexual selection is proposed to be an important driver of speciation and phenotypic diversification in animal systems. However, previous phylogenetic tests have produced conflicting results, perhaps because they have focused on a single signalling modality (visual ornaments), whereas sexual selection may act on alternative signalling modalities (e.g. acoustic ornaments). Here we compile phenotypic data from 259 avian sister species pairs to assess the relationship between visible plumage dichromatism—a standard index of sexual selection in birds—and macroevolutionary divergence in the other major avian signalling modality: song. We find evidence for a strong negative relationship between the degree of plumage dichromatism and divergence in song traits, which remains significant even when accounting for other key factors, including habitat type, ecological divergence and interspecific interactions. This negative relationship is opposite to the pattern expected by a straightforward interpretation of the sexual selection-diversification hypothesis, whereby higher levels of dichromatism indicating strong sexual selection should be related to greater levels of mating signal divergence regardless of signalling modality. Our findings imply a ‘trade-off’ between the elaboration of visual ornaments and the diversification of acoustic mating signals, and suggest that the effects of sexual selection on diversification can only be determined by considering multiple alternative signalling modalities
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