510 research outputs found
Risk evaluation of allergens in food production processes in function of proces-, product and installation parameters
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Clinical aspects of glucocorticoid sensitivity
Recent studies demonstrate that primary (hereditary) abnormalities in the glucocorticoid receptor gene make 6.6% of the normal population relatively 'hypersensitive' to glucocorticoids, while 2.3% are relatively 'resistant.' These abnormalities might explain why some individuals develop severe adverse effects during low dose glucocorticoid therapy, while others do not develop side effects even during long-term therapy with a much higher dose. Awareness of this heterogeneity in glucocorticoid sensitivity in the normal population might eventually allow the prediction of a 'safe' dose of glucocorticoid in individual patients. 'Resistance' to the beneficial clinical effects of glucocorticoid therapy in part of the patients with severe rheumatoid arthritis and asthma is probably rarely related to generalized primary (hereditary) glucocorticoid resistance. In the majority of patients this 'resistance' seems to be acquired and localized to the sites of inflammation, where it reflects high local cytokine production, which interferes with glucocorticoid action. Recognition of localized, acquired glucocorticoid resistance is of great importance indicating as alternative drug therapy with other immune-modulating drugs like cyclosporin and methotrexate. Chronic high dose glucocorticoid treatment in such patients is ineffective in alleviating symptomatology, while generalized side effects occur, reflecting the patient's normal systemic sensitivity to these drugs
arf3DS4: An Integrated Framework for Localization and Connectivity Analysis of fMRI Data
In standard fMRI analysis all voxels are tested in a massive univariate approach, that is, each voxel is tested independently. This requires stringent corrections for multiple comparisons to control the number of false positive tests (i.e., marking voxels as active while they are actually not). As a result, fMRI analyses may suffer from low power to detect activation, especially in studies with high levels of noise in the data, for example developmental or single-subject studies. Activated region fitting (ARF) yields a solution by modeling fMRI data by multiple Gaussian shaped regions. ARF only requires a small number of parameters and therefore has increased power to detect activation. If required, the estimated regions can be directly used as regions of interest in a functional connectivity analysis. ARF is implemented in the R package arf3DS4. In this paper ARF and its implementation are described and illustrated with an example
Predicting Progression to Parkinson's Disease Dementia Using Multivariate Normative Comparisons
Widespread CO2-rich cordierite in the UHT Bakhuis granulite belt, Surinam
The Bakhuis Granulite Belt, approx. 30 x 100 km, transects the large Paleoproterozoic greenstone belt along the north-eastern coast of South America. Part of the Granulite belt witnessed typical Ultrahigh-Temperature Metamorphism (UHTM). A metapelite area in the NE of the belt shows assemblages characteristic of UHTM: aluminous (up to 10 wt.%) orthopyroxene + sillimanite +/- sapphirine. Leucosomes commonly show mesoperthite or K-rich antiperthite. Ternary feldspar thermometry indicates a peak temperature of 1000-1050°C and pressure is estimated to have been around 9 kbar. Metapelites elsewhere in the belt lack mineral assemblages characteristic of UHTM. However, feldspar thermometry for these metapelites as well as for mesoperthite granulites indicates that peak temperatures were 900°C or higher throughout the belt and locally reached 1000-1050°C. It is, therefore, concluded that the other parts of the belt also witnessed UHTM, despite their lack of typical UHTM assemblages.
Study of peak assemblages in metapelites in these parts is hampered by varying, but usually considerable retrograde metamorphism. The main mafic mineral in metapelites is coarse Mg-rich cordierite, accompanied by coarse sillimanite. Widespread occurrence of cordierite + sillimanite in metapelites is unusual for UHTM, the more so as UHTM assemblages are commonly formed at the expense of cordierite-bearing assemblages. In a small part of the metapelites cordierite is accompanied by coarse aluminous (up to 9 wt.%) orthopyroxene. Associated cordierite and orthopyroxene appear to have formed in equilibrium with each other. Only the presence of aluminous orthopyroxene (as well as the presence of mesoperthite) is typical for UHTM, but is limited to a small part of the metapelites. Peak P-T conditions for the cordierite-bearing part of the belt are estimated to have been similar to those in the NE area with its characteristic UHTM assemblages. Primary and secondary fluid inclusions in UHT quartz blebs in orthopyroxene consist of pure CO2 and have a high density. Raman spectroscopy indicated a considerable CO2 content in cordierite. Estimated from their birefringence, the CO2 content of most cordierites is in the range of 1-2 wt.% CO2. This corresponds to a substantial filling of the cordierite channels with CO2 and for the higher levels possibly near-saturation with CO2 according to the model of Harley and Thompson for the maximum level of CO2 in cordierite. Thermodynamic data for CO2-rich cordierite are poorly known. However, a high level of CO2 in cordierite has been considered to lead to a substantial expansion of its stability field, also into the field of UHTM, at T > 900°C. This is, therefore, assumed to be the explanation for the unusual, widespread occurrence of cordierite in the UHTM belt.
A small part of the metapelite samples shows cordierite of a high birefringence, twice that of quartz. SIMS analysis of such cordierite showed 3.0 wt.% CO2, the highest level known from nature. The level is far too high to have formed at UHTM conditions according to the model of Harley and Thompson and would be possible only at conditions such as 700°C and 10 kbar. It is assumed that locally the CO2 level of cordierite changed after UHTM, by taking up additional CO2. Secondary fluid CO2 inclusions in UHT quartz have a higher density than the primary inclusions, indicating a near-isobaric cooling path down to 700-750°C. In these conditions cordierite probably could steadily re-equilibrate at decreasing temperature while taking up more and more CO2, up to 3 wt.% around 700°C.
The heat source for the UHTM in the Bakhuis Granulite belt is considered to be asthenospheric upwelling or mafic underplating, but mafic magmatism of identical age to the UHTM has not yet been found. One mafic intrusion was found to be around 20 Ma older than the UHTM, whereas in the SW of the belt numerous mafic intrusions formed around 70 Ma after UHTM
Formal Modeling of the Resistance to Peer Influence Questionnaire: A Comparison of Adolescent Boys and Girls With and Without Mild-to-Borderline Intellectual Disability
The Factor Structure of Cognitive Functioning in Cognitively Healthy Participants: a Meta-Analysis and Meta-Analysis of Individual Participant Data
Five patients with biochemical and/or clinical generalized glucocorticoid resistance without alterations in the glucocorticoid receptor gene
Five patients with biochemical and/or clinical generalized glucocorticoid resistance without alterations in the glucocorticoid receptor gene
Cortisol resistance (CR) is a rare disease characterized by a generalized
reduced sensitivity of end-organs to the actions of glucocorticoids (GCs)
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