75 research outputs found
Leukotriene D4 and platelet-activating factor-acether antagonists on allergic and arachidonic acid-induced reactions in guinea pig airways
Arachidonic acid (AA) and ovalbumin (OA) were used to induce contractions of sensitized guinea pig tracheal spiral (indomethacin-pretreated) and lung parenchymal strip preparations. This model was used to examine the properties of three leukotriene (LT) D4 antagonists and a platelet-activating factor (PAF)-acether receptor antagonist. The three LTD4 antagonists, L-649,923, FPL 57231, and LY163443, inhibited AA-induced contractions of indomethacin-pretreated tracheal spirals selectively. The PAF-acether antagonist, L-652,731, did not inhibit AA-induced contractions of either trachea or parenchyma. This confirmed that AA-induced contractions of trachea involved release and activity of LTD4. The LTD4 antagonists and L-652,731 partially inhibited OA-induced contractions of both trachea and parenchyma. When L-649,923 and L-652,731 or FPL 57231 and L-652,731 were combined, an additive inhibitory effect on OA-induced contractions was observed. When LY163443 and L-652,731 were combined, the inhibitory effect was synergistic. This may be due to the additional effect of LY163443 to inhibit phosphodiesterase. Total inhibition of OA-induced contractions was obtainable with relatively low concentrations when a LTD4 and PAF-acether antagonist were combined. These results suggested that LTD4 and PAF-acether may be the two major mediators in our model of allergic bronchospasm. The LTD4 and PAF-acether antagonists had the capacity to decrease baseline tone, even on tissues that were already relaxed with indomethacin, suggesting that LTD4 and PAF-acether may contribute to intrinsic tone in airway smooth muscle.LR: 20061115; PUBM: Print; JID: 0372712; 0 (Arachidonic Acids); 0 (Platelet Activating Factor); 0 (SRS-A); 506-32-1 (Arachidonic Acid); 53-86-1 (Indomethacin); 9006-59-1 (Ovalbumin); ppublishSource type: Electronic(1
Novel <i>STRA6</i> null mutations in the original family described with Matthew-Wood syndrome
GPFrontend and GPGraphics: graphical analysis tools for genetic association studies
Abstract Background Most software packages for whole genome association studies are non-graphical, purely text based programs originally designed to run with UNIX-like operating systems. Graphical output is often not intended or supposed to be performed with other command line tools, e.g. gnuplot. Results Using the Microsoft .NET 2.0 platform and Visual Studio 2005, we have created a graphical software package to analyze data from microarray whole genome association studies, both for a DNA-pooling based approach as well as regular single sample data. Part of this package was made to integrate with GenePool 0.8.2, a previously existing software suite for GNU/Linux systems, which we have modified to run in a Microsoft Windows environment. Further modifications cause it to generate some additional data. This enables GenePool to interact with the .NET parts created by us. The programs we developed are GPFrontend, a graphical user interface and frontend to use GenePool and create metadata files for it, and GPGraphics, a program to further analyze and graphically evaluate output of different WGA analysis programs, among them also GenePool. Conclusions Our programs enable regular MS Windows users without much experience in bioinformatics to easily visualize whole genome data from a variety of sources.</p
An Assessment of GUCA1C Variants in Primary Congenital Glaucoma
In the special issue “Molecular Genetics of Retinal Dystrophies”, Morales–Cámara and colleagues reported the association of a new candidate gene with primary congenital glaucoma (PCG) [...
Mitochondrial haplogroup U is associated with a reduced risk to develop exfoliation glaucoma in the German population
Abstract Background Various lines of evidence demonstrate the involvement of mitochondrial dysfunction in the pathogenesis of glaucoma. Therefore, mitochondrial DNA is a promising candidate for genetic susceptibility studies on glaucoma. To test the hypothesis that mitochondrial haplogroups influence the risk to develop glaucoma, we genotyped 12 single-nucleotide polymorphisms that define the European mitochondrial DNA haplogroups in healthy controls and two German patient cohorts with either exfoliation glaucoma or the normal tension subgroup of primary open angle glaucoma. Results Mitochondrial haplogroup U was significantly under-represented in patients with exfoliation glaucoma (8.3% compared with 18.9% in controls; p = 0.004). Conclusions People with haplogroup U have a lower risk to develop exfoliation glaucoma. Our results substantiate the suggestion that mitochondrial alterations have an impact on the etiology of glaucoma.</p
Pseudoexfoliation syndrome-associated genetic variants affect transcription factor binding and alternative splicing of LOXL1
Although lysyl oxidase-like 1 (LOXL1) is known as the principal genetic risk factor for pseudoexfoliation (PEX) syndrome, a major cause of glaucoma and cardiovascular complications, no functional variants have been identified to date. Here, we conduct a genome-wide association scan on 771 German PEX patients and 1,350 controls, followed by independent testing of associated variants in Italian and Japanese data sets. We focus on a 3.5-kb four-component polymorphic locus positioned spanning introns 1 and 2 of LOXL1 with enhancer-like chromatin features. We find that the rs11638944:C>G transversion exerts a cis-acting effect on the expression levels of LOXL1, mediated by differential binding of the transcription factor RXRα (retinoid X receptor alpha) and by modulating alternative splicing of LOXL1, eventually leading to reduced levels of LOXL1 mRNA in cells and tissues of risk allele carriers. These findings uncover a functional mechanism by which common noncoding variants influence LOXL1 expression. © The Author(s) 2017
Evaluation of nine candidate genes in patients with normal tension glaucoma: a case control study
Abstract Background Normal tension glaucoma is a major subtype of glaucoma, associated with intraocular pressures that are within the statistically normal range of the population. Monogenic forms following classical inheritance patterns are rare in this glaucoma subtype. Instead, multigenic inheritance is proposed for the majority of cases. The present study tested common sequence variants in candidate genes for association with normal tension glaucoma in the German population. Methods Ninety-eight SNPs were selected to tag the common genetic variation in nine genes, namely OPTN (optineurin), RDX (radixin), SNX16 (sorting nexin 16), OPA1 (optic atrophy 1), MFN1 (mitofusin 1), MFN2 (mitofusin 2), PARL (presenilin associated, rhomboid-like), SOD2 (superoxide dismutase 2, mitochondrial) and CYP1B1 (cytochrome P450, family 1, subfamily B, polypeptide 1). These SNPs were genotyped in 285 cases and 282 fully evaluated matched controls. Statistical analyses comprised single polymorphism association as well as haplogroup based association testing. Results Results suggested that genetic variation in five of the candidate genes (RDX, SNX16, OPA1, SOD2 and CYP1B1) is unlikely to confer major risk to develop normal tension glaucoma in the German population. In contrast, we observed a trend towards association of single SNPs in OPTN, MFN1, MFN2 and PARL. The SNPs of OPTN, MFN2 and PARL were further analysed by multimarker haplotype-based association testing. We identified a risk haplotype being more frequent in patients and a vice versa situation for the complementary protective haplotype in each of the three genes. Conclusion Common variants of OPTN, PARL, MFN1 and MFN2 should be analysed in other cohorts to confirm their involvement in normal tension glaucoma.</p
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