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61.
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63.
Esmeralda N Blaney Davidson Elly L Vitters Wim B van den Berg Peter M van der Kraan 《Arthritis research & therapy》2006,8(3):R65-8
Cartilage damage in osteoarthritis (OA) is considered an imbalance between catabolic and anabolic factors, favoring the catabolic
side. We assessed whether adenoviral overexpression of transforming growth factor-β (TGFβ) enhanced cartilage repair and whether
TGFβ-induced fibrosis was blocked by local expression of the intracellular TGFβ inhibitor Smad7. We inflicted cartilage damage
by injection of interleukin-1 (IL-1) into murine knee joints. After 2 days, we injected an adenovirus encoding TGFβ. On day
4, we measured proteoglycan (PG) synthesis and content. To examine whether we could block TGFβ-induced fibrosis and stimulate
cartilage repair simultaneously, we injected Ad-TGFβ and Ad-Smad7. This was performed both after IL-1-induced damage and in
a model of primary OA. In addition to PG in cartilage, synovial fibrosis was measured by determining the synovial width and
the number of procollagen I-expressing cells. Adenoviral overexpression of TGFβ restored the IL-1-induced reduction in PG
content and increased PG synthesis. TGFβ-induced an elevation in PG content in cartilage of the OA model. TGFβ-induced synovial
fibrosis was strongly diminished by simultaneous synovial overexpression of Smad7 in the synovial lining. Of great interest,
overexpression of Smad7 did not reduce the repair-stimulating effect of TGFβ on cartilage. Adenoviral overexpression of TGFβ
stimulated repair of IL-1- and OA-damaged cartilage. TGFβ-induced synovial fibrosis was blocked by locally inhibiting TGFβ
signaling in the synovial lining by simultaneously transfecting it with an adenovirus overexpressing Smad7. 相似文献
64.
Twelve new species of Polycystididae Graff, 1905 are described from the Australian east coast. Nine of them could not be placed
in any of the existing genera, and therefore six new genera are erected. Alchoides n. gen. differs from all other polycystidid genera by the presence of a bundle of glands that opens into the distal part
of the male atrium (accessory vesicle type V). Two species are included in the genus, A. alchoides n. sp. and A. dittmannae n. sp., which differ from each other in the shape of the stylet. Ametochus gehrkei n. gen n. sp. can be distinguished from other polycystidids by the presence of a prostate vesicle type III associated with
a prostate stylet type III, combined with the presence of an accessory stylet type III, while a prostate stylet type II is
lacking. Typical for Arrawarria inexpectata n. gen n. sp. is the combined presence of an armed cirrus with a prostate vesicle type II connected to a prostate stylet
type II. Two species are assigned to the new genus Duplexostylus n. gen.: D. rowei n. sp. and D. winsori n. sp. These two species have two unique features: a prostate vesicle type IV directly connected to a prostate stylet type
III and an asymmetrical septum that surrounds the proximal part of the male atrium. They can be distinguished from each other
by differences in the detailed construction of their stylets. Two new species are placed in the new genus Stradorhynchus n. gen.: S. caecus n. sp. and S. terminalis n. sp. They have unpaired gonads and a prostate vesicle type IV connected to a prostate stylet type IV, which combination
of characters makes them unique within the Polycystididae. The two species differ from each other in the shape and size of
the stylet. Triaustrorhynchus armatus n. gen., n. sp. is the first species of the Polycystididae to have three types of stylet in the male atrium: a prostate stylet
type II, a prostate stylet type III and an accessory stylet type III. Three new species could be placed in existing genera:
Cincturorhynchus monaculeus n. sp., Paraustrorhynchus caligatus n. sp. and Polycystis australis n. sp. All three differ from their congeners in the form and dimensions of their stylets. All newly described species are
discussed, giving their similarities and differences with resembling species. Austrorhynchus hawaiiensis Karling, 1977 is reported for the first time in Australia, and the Australian population is compared with populations from
other regions. The presence of Gyratrix hermaphroditus Ehrenberg, 1831, one new species of Paulodora Marcus, 1948 and a new genus of Typhlopolycystidinae Evdonin, 1977 is mentioned. 相似文献
65.
Frederik A. R. Muylle Dirk Adriaensen Wim De Coen Jean-Pierre Timmermans Ronny Blust 《Biometals》2006,19(4):437-450
Intracellular zinc levels are homeostatically regulated and although most is bound, a pool of labile Zn(II) is present in
cells. We show here that the zinc probe FluoZin-3 is useful to monitor zinc fluxes during fluorescent imaging of the trout
hepatic cell line D11. Nuclei and bulk cytosol appeared to lack detectable labile zinc, while the punctuate staining pattern
colocalized with a lysosome-specific probe. Applying extracellular zinc alone resulted in vesicular sequestration of the metal
ion. Together with Na-pyrithione a delayed and toxic rise in cellular fluorescence was triggered. When using another ionophore,
4-Br A23187, a zinc buffering effect of the vesicular pools was evident. Secondly, N-ethylmaleimide induced a homogeneous fluorescence rise, which was strongly enhanced by addition of Zn-pyrithione and disappeared
after TPEN washing. This suggests the involvement of thiol residues in controlling available cytosolic zinc. Our observations
have implications for the interpretation of calculated intracellular Zn2+ concentrations. 相似文献
66.
Ping Wang Paul P.C.A. Menheere Arne Astrup Malene R. Andersen Marleen A. van Baak Thomas M. Larsen Susan Jebb Anthony Kafatos Andreas F.H. Pfeiffer J. Alfredo Martinez Teodora Handjieva‐Darlenska Petr Hlavaty Nathalie Viguerie Dominique Langin Wim H.M. Saris Edwin C.M. Mariman Diogenes consortium 《Obesity (Silver Spring, Md.)》2013,21(10):1997-2006
67.
Linda IJsselstijn Janne M. Papma Lennard J. M. Dekker Wim Calame Christoph Stingl Peter J. Koudstaal Niels D. Prins Peter A. E. Sillevis Smitt Theo M. Luider 《Proteomics》2013,13(16):2526-2533
We have explored proteins related to mild cognitive impairment (MCI). The serum proteome of 35 amnestic MCI patients and 35 cognitively healthy persons was investigated by LC MS. We identified 108 differentially expressed peptides between MCI patients and controls, belonging to 39 proteins. Eight proteins were selected for further investigation by quantitative protein measurements using a MRM assay; apolipoprotein E, carboxypeptidase N subunit 2, complement factor B (CFAB), galectin‐3 binding protein (LG3BP), lumican, serum amyloid A‐4 protein (SAA4), serum amyloid P‐component, and sex hormone binding globulin. Results of the quantitative protein measurements showed significantly decreased levels of carboxypeptidase N subunit 2, CFAB, LG3BP, SAA4, and serum amyloid P‐component in serum from amnestic MCI patients compared with cognitive healthy controls (two‐sided t‐test; p < 0.05). Apolipoprotein E and lumican showed no significant difference in protein levels, sex hormone binding globulin could not be quantified since the MRM assay did not reach the required sensitivity. A model based on the three most significantly decreased proteins (CFAB, LG3BP, and SAA4) showed a sensitivity and specificity of 73 and 66%, respectively, for the initial sample set. A small external validation set yielded 77% sensitivity and 75% specificity. 相似文献
68.
Evolutionary psychologists have suggested that our brain is composed of evolved mechanisms. One extensively studied mechanism is the cheater detection module. This module would make people very good at detecting cheaters in a social exchange. A vast amount of research has illustrated performance facilitation on social contract selection tasks. This facilitation is attributed to the alleged automatic and isolated operation of the module (i.e., independent of general cognitive capacity). This study, using the selection task, tested the critical automaticity assumption in three experiments. Experiments 1 and 2 established that performance on social contract versions did not depend on cognitive capacity or age. Experiment 3 showed that experimentally burdening cognitive resources with a secondary task had no impact on performance on the social contract version. However, in all experiments, performance on a non-social contract version did depend on available cognitive capacity. Overall, findings validate the automatic and effortless nature of social exchange reasoning. 相似文献
69.
70.
Saskia Vanderhaegen Marcus Fislage Katarzyna Domanska Wim Versées Els Pardon Vittorio Bellotti Jan Steyaert 《Protein science : a publication of the Protein Society》2013,22(10):1349-1357
To investigate early intermediates of β2‐microglobulin (β2m) amyloidogenesis, we solved the structure of β2m containing the amyloidogenic Pro32Gly mutation by X‐ray crystallography. One nanobody (Nb24) that efficiently blocks fibril elongation was used as a chaperone to co‐crystallize the Pro32Gly β2m monomer under physiological conditions. The complex of P32G β2m with Nb24 reveals a trans peptide bond at position 32 of this amyloidogenic variant, whereas Pro32 adopts the cis conformation in the wild‐type monomer, indicating that the cis to trans isomerization at Pro32 plays a critical role in the early onset of β2m amyloid formation. 相似文献