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排序方式: 共有123条查询结果,搜索用时 171 毫秒
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Carl PC Chen Chih-Chin Hsu Wen-Lin Yeh Hsiu-Chu Lin Sen-Yung Hsieh Shih-Cherng Lin Tai-Tzung Chen Max JL Chen Simon FT Tang 《Proteome science》2011,9(1):1-10
Background
Prenatal screening for Down Syndrome (DS) would benefit from an increased number of biomarkers to improve sensitivity and specificity. Improving sensitivity and specificity would decrease the need for potentially risky invasive diagnostic procedures.Results
We have performed an in depth two-dimensional difference gel electrophoresis (2D DIGE) study to identify potential biomarkers. We have used maternal plasma samples obtained from first and second trimesters from mothers carrying DS affected fetuses compared with mothers carrying normal fetuses. Plasma samples were albumin/IgG depleted and expanded pH ranges of pH 4.5 - 5.5, pH 5.3 - 6.5 and pH 6 - 9 were used for two-dimensional gel electrophoresis (2DE). We found no differentially expressed proteins in the first trimester between the two groups. Significant up-regulation of ceruloplasmin, inter-alpha-trypsin inhibitor heavy chain H4, complement proteins C1s subcomponent, C4-A, C5, and C9 and kininogen 1 were detected in the second trimester in maternal plasma samples where a DS affected fetus was being carried. However, ceruloplasmin could not be confirmed as being consistently up-regulated in DS affected pregnancies by Western blotting.Conclusions
Despite the in depth 2DE approach used in this study the results underline the deficiencies of gel-based proteomics for detection of plasma biomarkers. Gel-free approaches may be more productive to increase the number of plasma biomarkers for DS for non-invasive prenatal screening and diagnosis. 相似文献13.
Plant Molecular Biology - 相似文献
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Jamil M Neto Marina GM Viturino Galina Ananina Flvia F Bajano Sueli M da S Costa Alicia B Roque Gessica FS Borges Raissa Franchi Priscila HH Rim Flvio M Medina Fernando F Costa Mnica B de Melo Jos PC de Vasconcellos 《Experimental biology and medicine (Maywood, N.J.)》2021,246(21):2290
This study aimed to investigate the association among genetic variants of the complement pathway CFB R32Q (rs641153), C3 R102G (rs2230199), and CFH (rs1410996) with age-related macular degeneration (AMD) in a sample of the Brazilian population. In a case-control study, 484 AMD patients were classified according to the clinical age-related maculopathy grading system (CARMS) and compared to 479 unrelated controls. The genetic variants rs1410996 of complement H (CFH), rs641153 of complement factor B (CFB), and rs2230199 of complement 3 (C3) were evaluated through polymerase chain reaction (PCR) and direct sequencing. The associations between single nucleotide polymorphisms (SNPs) and AMD, adjusted by age, were assessed by using logistic regression models. A statistically significant association was observed between AMD risk and rs2230199 variant with an OR of 2.01 (P = 0.0002) for CG individuals compared to CC individuals. Regarding the comparison of advanced AMD versus the control group, the OR was 2.12 (P = 0.0036) for GG versus AA genotypes for rs1410996 variant. Similarly, the OR for rs2230199 polymorphism was 2.3034 (P = 5.47e-05) when comparing CG individuals to CC carriers. In contrast, the rs641153 variant showed a significant protective effect against advanced AMD for GA versus GG genotype (OR = 0.4406; P = 0.0019). When comparing wet AMD versus controls, a significant association was detected for rs1410996 variant (OR = 2.16; P = 0.0039) comparing carriers of the homozygous GG versus AA genotype, as well as in the comparisons of GG (OR = 3.0713; P = 0.0046) and CG genotypes (OR = 2.2249; P = 0.0002) versus CC genotype for rs2230199 variant, respectively. The rs641153 variant granted a significant protective effect against wet AMD for GA versus GG genotypes (OR = 0.4601; P = 0.0044). Our study confirmed the risk association between rs2230199 and rs1410996 variants and AMD, and the protective role against AMD for rs641153 variant. 相似文献
17.
Martijn F Schenk Jan HG Cordewener Antoine HP America Wendy PC van't Westende Marinus JM Smulders Luud JWJ Gilissen 《BMC plant biology》2009,9(1):24
Background
Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula) have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MSE was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome. 相似文献18.
Rachel Knevel Diederik PC de Rooy Tore Saxne Elisabet Lindqvist Martha K Leijsma Nina A Daha Bobby PC Koeleman Roula Tsonaka Jeanine J Houwing-Duistermaat Joris JM Schonkeren Rene EM Toes Tom WJ Huizinga Elisabeth Brouwer Anthony G Wilson Annette HM van der Helm-van Mil 《Arthritis research & therapy》2014,16(3):R108
Introduction
Progression of joint destruction in rheumatoid arthritis (RA) is partly heritably; 45 to 58% of the variance in joint destruction is estimated to be explained by genetic factors. The binding of RANKL (Receptor Activator for Nuclear Factor κ B Ligand) to RANK results in the activation of TRAF6 (tumor necrosis factor (TNF) receptor associated factor-6), and osteoclast formation ultimately leading to enhanced bone resorption. This bone resorption is inhibited by osteoprotegerin (OPG) which prevents RANKL-RANK interactions. The OPG/RANK/RANKL/TRAF6 pathway plays an important role in bone remodeling. Therefore, we investigated whether genetic variants in OPG, RANK, RANKL and TRAF6 are associated with the rate of joint destruction in RA.Methods
1,418 patients with 4,885 X-rays of hands and feet derived from four independent data-sets were studied. In each data-set the relative increase of the progression rate per year in the presence of a genotype was assessed. First, explorative analyses were performed on 600 RA-patients from Leiden. 109 SNPs, tagging OPG, RANK, RANKL and TRAF6, were tested. Single nucleotide polymorphisms (SNPs) significantly associated in phase-1 were genotyped in data-sets from Groningen (Netherlands), Sheffield (United Kingdom) and Lund (Switzerland). Data were summarized in an inverse weighted variance meta-analysis. Bonferonni correction for multiple testing was applied.Results
We found that 33 SNPs were significantly associated with the rate of joint destruction in phase-1. In phase-2, six SNPs in OPG and four SNPs in RANK were associated with progression of joint destruction with P-value <0.05. In the meta-analyses of all four data-sets, RA-patients with the minor allele of OPG-rs1485305 expressed higher rates of joint destruction compared to patients without these risk variants (P = 2.35x10−4). This variant was also significant after Bonferroni correction.Conclusions
These results indicate that a genetic variant in OPG is associated with a more severe rate of joint destruction in RA. 相似文献19.
A scanning calorimetric study of unfolding equilibria in homodimeric chicken gizzard tropomyosins. 总被引:1,自引:0,他引:1 下载免费PDF全文
Using both circular dichroism (CD) and differential scanning calorimetry (DSC), several laboratories find that the thermal unfolding transitions of alpha alpha and beta beta homodimeric coiled coils of rabbit tropomyosin are multistate and display an overall unfolding enthalpy of near 300 kcal (mol dimer)(-1). In contrast, an extant CD study of beta beta and gamma gamma species of chicken gizzard tropomyosin concludes that their unfolding transitions are simple two-state transitions, with much smaller overall enthalpies (98 kcal mol(-1) for beta beta and 162 kcal mol(-1) for gamma gamma). However, these smaller enthalpies have been questioned, because they imply a concentration dependence of the melting temperatures that is far larger than observed by CD. We report here DSC studies of the unfolding of both beta beta and gamma gamma chicken gizzard homodimers. The results show that these transitions are very similar to those in rabbit tropomyosins in that 1) the overall unfolding enthalpy is near 300 kcal mol(-1); 2) the overall delta C(rho) values are significantly positive; 3) the various transitions are multistate, requiring at least two and as many as four domains to fit the DSC data. DSC studies are also reported on these homodimeric species of chicken gizzard tropomyosin with a single interchain disulfide cross-link. These results are also generally similar to those for the correspondingly cross-linked rabbit tropomyosins. 相似文献
20.
Complementation Mapping of Skeletal and Central Nervous System Abnormalities in Mice of the Piebald Deletion Complex 总被引:5,自引:1,他引:4 下载免费PDF全文
The s(15DttMb), s(36Pub), s(1Acrg) and s(24Pub) piebald deletion alleles belong to a set of overlapping deficiencies on the distal portion of chromosome 14. Molecular analysis was used to define the extent of the deletions. Mice homozygous for the smallest deletion, s(15DttMb), die shortly after delivery and display alterations in the central nervous system, including hydrocephalus and a dorsally restricted malformation of the spinal cord. These mice also display homeotic transformations of vertebrae in the midthoracic and lumbar regions. Homozygous s(27Pub) mice contain a point mutation in the piebald gene, survive to weaning, and display no central nervous system or skeletal defects, arguing that the s(15DttMb) phenotype results from the loss of genes in addition to piebald. A larger deletion, s(36Pub), exhibits additional cartilage malformations and defects in the anterior axial and cranial skeleton. The skeletal defects in both s(15DttMb) and s(36Pub) mice resemble transformations associated with the targeted disruption of Hox genes and genes encoding the retinoic acid receptors, which play a role in the specification of segmental identity along the anteroposterior axis. Complementation analysis of the s(15DttMb) and s(36Pub) phenotypes, using two additional deletions, localized the gene(s) associated with each phenotype to a defined chromosomal region. 相似文献