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151.
152.
Lara Bossini-Castillo Carmen P Simeon Lorenzo Beretta Jasper C Broen Madelon C Vonk Raquel Ríos-Fernández Gerard Espinosa Patricia Carreira María T Camps Maria J Castillo Miguel A González-Gay Emma Beltrán María del Carmen Freire Javier Narváez Carlos Tolosa Torsten Witte Alexander Kreuter Annemie J Schuerwegh Anna-Maria Hoffmann-Vold Roger Hesselstrand Claudio Lunardi Jacob M van Laar Meng May Chee Ariane Herrick Bobby PC Koeleman Christopher P Denton Carmen Fonseca Timothy RDJ Radstake Javier Martin 《Arthritis research & therapy》2012,14(2):1-7
Idiopathic inflammatory myopathies (IIMs) comprise a group of autoimmune diseases that are characterized by symmetrical skeletal muscle weakness and muscle inflammation with no known cause. Like other autoimmune diseases, IIMs are treated with either glucocorticoids or immunosuppressive drugs. However, many patients with an IIM are frequently resistant to immunosuppressive treatments, and there is compelling evidence to indicate that not only adaptive immune but also several non-immune mechanisms play a role in the pathogenesis of these disorders. Here, we focus on some of the evidence related to pathologic mechanisms, such as the innate immune response, endoplasmic reticulum stress, non-immune consequences of MHC class I overexpression, metabolic disturbances, and hypoxia. These mechanisms may explain how IIM-related pathologic processes can continue even in the face of immunosuppressive therapies. These data indicate that therapeutic strategies in IIMs should be directed at both immune and non-immune mechanisms of muscle damage. 相似文献
153.
154.
Koen Nelissen Olivier Joly Jean-Baptiste Durand James T. Todd Wim Vanduffel Guy A. Orban 《PloS one》2009,4(12)
We used contrast-agent enhanced functional magnetic resonance imaging (fMRI) in the alert monkey to map the cortical regions involved in the extraction of 3D shape from the monocular static cues, texture and shading. As in the parallel human imaging study [1], we contrasted the 3D condition to several 2D control conditions. The extraction of 3D shape from texture (3D SfT) involves both ventral and parietal regions, in addition to early visual areas. Strongest activation was observed in CIP, with decreasing strength towards the anterior part of the intraparietal sulcus (IPS). In the ventral stream 3D SfT sensitivity was observed in a ventral portion of TEO. The extraction of 3D shape from shading (3D SfS) involved predominantly ventral regions, such as V4 and a dorsal potion of TEO. These results are similar to those obtained earlier in human subjects and indicate that the extraction of 3D shape from texture is performed in both ventral and dorsal regions for both species, as are the motion and disparity cues, whereas shading is mainly processed in the ventral stream. 相似文献
155.
Phylogenetic relationships among prokaryotic and eukaryotic catalases 总被引:13,自引:1,他引:12
Seventy-four catalase protein sequences, including 29 bacterial, 8 fungal,
7 animal, and 30 plant sequences, were compiled, and 70 were used for
phylogenetic reconstruction. The core of the resulting tree revealed
unique, separate groups of plant and animal catalases, two groups of fungal
catalases, and three groups of bacterial catalases. The only overlap of
kingdoms occurred within one branch and involved fungal and bacterial
large-subunit enzymes. The other fungal branch was closely linked to the
group of animal enzymes. Group I bacterial catalases were more closely
related to the plant enzymes and contained such diverse taxa as the
Gram-positive Listeria seeligeri, Deinocococcus radiodurans, and
gamma-proteobacteria. Group III bacterial sequences were more closely
related to fungal and animal sequences and included enzymes from a broad
range of bacteria including high- and low-GC Gram positives,
proteobacteria, and a bacteroides species. Group II was composed of
large-subunit catalases from diverse sources including Gram positives
(low-GC Bacilli and high-GC Mycobacteria), proteobacteria, and species of
the filamentous fungus Aspergillus. These data can be interpreted in terms
of two gene duplication events that produced a minimum of three catalase
gene family members that subsequently evolved in response to environmental
demands. Horizontal gene transfer may have been responsible for the group
II mixture of bacterial and fungal large-subunit catalases.
相似文献
156.
A solid-state deuterium NMR investigation of conformation and order in magnetically oriented [d(CGCGAATTCGCG)]2 总被引:1,自引:0,他引:1
Solid-state deuterium NMR has been used to investigate the oriented liquid crystal phase of the hydrated oligonucleotide [d(CGCGAATTCGCG)]2. Previous investigations have shown that the helix axis is aligned perpendicular to the magnetic field, while at reduced temperatures motion about the helix axis is eliminated. Synthetic oligonucleotide samples incorporating different labeled nucleosides, [2"-2H]-2'-deoxyadenosine, [methyl-2H]thymidine, [8-2H]-2'-deoxyguanosine, and [8-2H]-2'-deoxyadenosine, permitted investigation of both the base and sugar conformation and ordering in the aligned phase. From line-shape analysis of the purine-labeled samples the orientation of the base C8 C-D bond with respect to the helix axis was determined to be theta = 90 degrees with a distribution of sigma total = 20 degrees, which is comparable to the orientation of theta = 90 degrees, sigma total = 15 degrees, with an oriented fraction P = 0.7 found for the C3 symmetry axis of the methyl-labeled dodecamer. The orientation of the sugar 2" C-D bond with respect to the helix axis is theta = 22 degrees with a distribution of sigma total = 15 degrees in agreement with the expected C2'-endo sugar conformation. The fraction of C3'-endo was also investigated and from analysis of line shape cannot exceed 20%. These results, though preliminary in nature, illustrate the application of this aligned phase for structural investigations. 相似文献
157.
Deuterium NMR investigation of backbone dynamics in the synthetic oligonucleotide [d(CGCGAATTCGCG)]2 总被引:2,自引:0,他引:2
Backbone dynamics in the [5',5"-2H2]2'-deoxythymidine labeled duplex dodecamer [d-(CGCGAAT*T*CGC)]2 have been investigated by solid-state 2H NMR. Quadrupolar echo line shapes, spin-lattice relaxation, and quadrupolar echo decay times were obtained over hydration levels ranging from W = 0.0 to 25.2 (moles of H2O/mole of nucleotide). Variation of the line shape with changing hydration level was analyzed by using models employed in previous investigations of dodecamer base and sugar dynamics. Both fast local motions and a slower helix motion were present within the oligonucleotide. The fast motion was modeled as a four-site libration whose amplitude increased with hydration level. The root mean square amplitude of this librational model was 2-6 degrees larger than the amplitude observed in either the furanose ring or base labeled material for the entire range of hydration levels investigated. The observed line shape was inconsistent with a rapid three-site trans-gauche isomerization. A slow motion about the helix axis was observed at low water levels and increased in rate and amplitude with hydration. This motional model is in agreement with previous oligonucleotide studies. 相似文献
158.
159.
Background
Efficient natural transformation in Neisseria requires the presence of short DNA uptake sequences (DUSs). Doubts remain whether DUSs propagate by pure selfish molecular drive or are selected for 'safe sex' among conspecifics. 相似文献160.