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51.
Kristof Notelaers Susana Rocha Rik Paesen Nina Swinnen Jeroen Vangindertael Jochen C. Meier Jean-Michel Rigo Marcel Ameloot Johan Hofkens 《Histochemistry and cell biology》2014,142(1):79-90
In this study, the effect of glycine receptor (GlyR) α3 alternative RNA splicing on the distribution of receptors in the membrane of human embryonic kidney 293 cells is investigated using optical super-resolution microscopy. Direct stochastic optical reconstruction microscopy is used to image both α3K and α3L splice variants individually and together using single- and dual-color imaging. Pair correlation analysis is used to extract quantitative measures from the resulting images. Autocorrelation analysis of the individually expressed variants reveals clustering of both variants, yet with differing properties. The cluster size is increased for α3L compared to α3K (mean radius 92 ± 4 and 56 ± 3 nm, respectively), yet an even bigger difference is found in the cluster density (9,870 ± 1,433 and 1,747 ± 200 μm?2, respectively). Furthermore, cross-correlation analysis revealed that upon co-expression, clusters colocalize on the same spatial scales as for individually expressed receptors (mean co-cluster radius 94 ± 6 nm). These results demonstrate that RNA splicing determines GlyR α3 membrane distribution, which has consequences for neuronal GlyR physiology and function. 相似文献
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RAMPs (receptor activity-modifying proteins) were discovered in 1998 as accessory proteins needed to the functionnal activity of CGRP (calcitonin gene-related peptide) receptors. Three RAMPs generated by three different genes are known in human, rat and mice. The coding sequences of such genes are described, but as yet, regulation sequences are unknown. RAMPs interact with GPCR (G protein-coupled receptors) of class II. In the case of the calcitonin/CGRP peptide family, RAMPs determine the functionnal specificity of the receptor, glycosylate and translocate the receptor to the cell surface. CGRP receptors are observed in presence of the RAMP1/calcitonin receptor-like receptor (CRLR), but the association of RAMP2 or RAMP3 with CRLR generates an adrenomedullin receptor. The calcitonin receptor (CTR) is translocated alone to the cell surface, but interactions of RAMPs with CTR forms amylin receptors. If RAMPs can interact with glucagon, parathyroid hormone and VIP/PACAP (vasoactive intestinal peptide/pituitary adenylate cyclase activating polypeptide (VPACR1)) receptors, the functionnal specificity of these receptors remains unaltered. However, the complex VPACR1/RAMP2 enhances specifically the phosphoinoside signaling pathway. 相似文献
55.
Palmer G Burger D Mezin F Magne D Gabay C Dayer JM Guerne PA 《Arthritis research & therapy》2004,6(3):R181-R189
Leflunomide is an immunomodulatory agent used for the treatment of rheumatoid arthritis. In this study, we investigated the
effect of A77 1726 – the active metabolite of leflunomide – on the production of IL-1 receptor antagonist (IL-1Ra) by human
synovial fibroblasts and articular chondrocytes. Cells were incubated with A77 1726 alone or in combination with proinflammatory
cytokines. IL-1Ra production was determined by ELISA. A77 1726 alone had no effect, but in the presence of IL-1β or tumour
necrosis factor-α it markedly enhanced the secretion of IL-1Ra in synovial fibroblasts and chondrocytes. The effect of A77
1726 was greatest at 100 μmol/l. In synovial fibroblasts and de-differentiated chondrocytes, A77 1726 also increased IL-1β-induced
IL-1Ra production in cell lysates. Freshly isolated chondrocytes contained no significant amounts of intracellular IL-1Ra.
A77 1726 is a known inhibitor of pyrimidine synthesis and cyclo-oxygenase (COX)-2 activity. Addition of exogenous uridine
did not significantly modify the effect of A77 1726 on IL-1Ra production, suggesting that it was not mediated by inhibition
of pyrimidine synthesis. Indomethacin increased IL-1β-induced IL-1Ra secretion in synovial fibroblasts and de-differentiated
chondrocytes, suggesting that inhibition of COX-2 may indeed enhance IL-1β-induced IL-1Ra production. However, the stimulatory
effect of indomethacin was consistently less effective than that of A77 1726. A77 1726 increases IL-1Ra production by synovial
fibroblasts and chondrocytes in the presence of proinflammatory cytokines, and thus it may possess chondroprotective effects.
The effect of A77 1726 may be partially mediated by inhibition of COX-2, but other mechanisms likely concur to stimulate IL-1Ra
production. 相似文献
56.
Marcus Clauss Hanspeter Steinmetz Ulrike Eulenberger Pete Ossent Robert Zingg Jürgen Hummel Jean-Michel Hatt 《European Journal of Wildlife Research》2007,53(1):68-72
The digestive tract of elephants is surprisingly short compared to other herbivorous mammals. However, measurements relating
the length of the intestine to the body mass of the respective individual are rare. In this study, we report such data for
an African elephant and an Asian elephant. Our data support the hypothesis that Asian elephants have a longer intestinal tract
than their African counterparts. These findings are in accord with the observation of longer retention times and higher digestion
coefficients in Asian as compared to African elephants. This difference between the species could be the reflection of slightly
different ecological niches, with Asian elephants adapted to a natural diet with a higher proportion of grass. 相似文献
57.
A full saturated linkage map of<Emphasis Type="Italic"> Picea abies</Emphasis> including AFLP,SSR, ESTP, 5S rDNA and morphological markers 总被引:3,自引:0,他引:3
Acheré V Faivre-Rampant P Jeandroz S Besnard G Markussen T Aragones A Fladung M Ritter E Favre JM 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(8):1602-1613
Based on an F1 progeny of 73 individuals, two parental maps were constructed according to the double pseudo-test cross strategy. The paternal map contained 16 linkage groups for a total genetic length of 1,792 cM. The maternal map covered 1,920 cM, and consisted of 12 linkage groups. These parental maps were then integrated using 66 intercross markers. The resulting consensus map covered 2,035 cM and included 755 markers (661 AFLPs, 74 SSRs, 18 ESTPs, the 5S rDNA and the early cone formation trait) on 12 linkage groups, reflecting the haploid number of chromosomes of Picea abies. The average spacing between two adjacent markers was 2.6 cM. The presence of 39 of the SSR and/or ESTP markers from this consensus map on other published maps of different Picea and Pinus species allowed us to establish partial linkage group homologies across three P. abies maps (up to five common markers per linkage group). This first saturated linkage map of P. abies could be therefore used as a support for developing comparative genome mapping in conifers.Communicated by O. Savolainen 相似文献
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59.
Ghislain Bidaut Karsten Suhre Jean-Michel Claverie Michael F Ochs 《BMC bioinformatics》2006,7(1):1-12
Background
The Tissue Microarray (TMA) facilitates high-throughput analysis of hundreds of tissue specimens simultaneously. However, bottlenecks in the storage and manipulation of the data generated from TMA reviews have become apparent. A number of software applications have been developed to assist in image and data management; however no solution currently facilitates the easy online review, scoring and subsequent storage of images and data associated with TMA experimentation.Results
This paper describes the design, development and validation of the Virtual Tissue Matrix (VTM). Through an intuitive HTML driven user interface, the VTM provides digital/virtual slide based images of each TMA core and a means to record observations on each TMA spot. Data generated from a TMA review is stored in an associated relational database, which facilitates the use of flexible scoring forms. The system allows multiple users to record their interpretation of each TMA spot for any parameters assessed. Images generated for the VTM were captured using a standard background lighting intensity and corrective algorithms were applied to each image to eliminate any background lighting hue inconsistencies or vignetting. Validation of the VTM involved examination of inter-and intra-observer variability between microscope and digital TMA reviews. Six bladder TMAs were immunohistochemically stained for E-Cadherin, β-Catenin and PhosphoMet and were assessed by two reviewers for the amount of core and tumour present, the amount and intensity of membrane, cytoplasmic and nuclear staining.Conclusion
Results show that digital VTM images are representative of the original tissue viewed with a microscope. There were equivalent levels of inter-and intra-observer agreement for five out of the eight parameters assessed. Results also suggest that digital reviews may correct potential problems experienced when reviewing TMAs using a microscope, for example, removal of background lighting variance and tint, and potential disorientation of the reviewer, which may have resulted in the discrepancies evident in the remaining three parameters. 相似文献60.
Henri Debray Danuta Dus Jean-Michel Wieruszeski Gérard Strecker Jean Montreuil 《Glycoconjugate journal》1991,8(1):29-37
Four bi-antennary glycan fractions of theN-acetyllactosamine-type, derived from a Lewis lung carcinoma (LL2) cell subline resistant to theAleuria aurantia agglutinin were studied by 400 MHz1H-NMR spectroscopy. By this method, their antennae were found to be terminated either by (2-3 or 6)-linkedN-acetylneuraminic acid or (1-3)-linked galactose residues. The primary structure of glycans of these four glycopeptide or derived oligosaccharide-alditols has been determined in full detail.Abbreviations NAc
N-acetyl group
- NGc
N-glycolyl group
- GlcNAc
N-acetylglucosamine
- NeuAc
N-acetylneuraminic acid
- NeuGc
N-glycolylneuraminic acid
- Man
mannose
- Gal
galactose
- Fuc
fucose
- Con A
concanavalin A
- LCA
Lens culinaris agglutinin
- AAA
Aleuria aurantia agglutinin
- WGA
Wheat germ agglutinin
- RCA II
Ricinus communis agglutinin II
- PBS
phosphate buffered saline, 0.01m Na2HPO4/0.14m NaCl, pH 7.2
- HPLC
high performance liquid chromatography
- EMEM
Eagle's Minimal Essential Medium
- LecR
lectin resistant
- MG
-methylglycoside 相似文献