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21.
Lamari FN Karamanos NK 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,781(1-2):3-19
Sialic acids are biosynthesized by almost all organisms as a 9-carbon carboxylated monosaccharide and are integral components of glycoconjugates. More than 40 naturally occurring sialic acid derivatives of the three main forms of sialic acids, the N-acetyl- and N-glycolylneuraminic acid and 2-keto-3-deoxy-nonulosonic acid have been identified. Due to the great importance of sialic acids as key mediators in a plethora of cellular events, including cell-cell recognition and cell-matrix interactions, their analysis in biologic samples is useful for a deeper understanding of the various (patho)physiological processes and of value in disease diagnosis and monitoring. In this review we summarize the methodology developed to isolate and liberate sialic acids from biologic samples as well as the chromatographic, electromigration and hyphenated techniques available for their separation and analysis. A critical evaluation of the biological relevance of the results obtained by analyzing sialic acids in biologic samples is also presented. 相似文献
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A case-control study was conducted to determine the diagnostic value of Chlamydia trachomatis-associated anti-Chsp10 and/or anti-Chsp60 antibodies in the detection of secondary infertility. There were significant associations between C. trachomatis infection and infertility (p<0.01), and between C. trachomatis-specific anti-Chsp10 or anti-Chsp60 antibodies and secondary infertility (p<0.001). A significant correlation was found between anti-Chsp10 and anti-Chsp60 titers (p<0.01). The detection of either C. trachomatis-associated anti-Chsp10 or anti-Chsp60 antibodies cumulatively allowed specific diagnosis of secondary infertility (57.4% sensitivity, 75.5% specificity). 相似文献
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Spyros D. Georgatos Fotini Gounari Susann Remington 《BioEssays : news and reviews in molecular, cellular and developmental biology》1994,16(6):413-418
The elongated fiber cells of the eye lens contain a unique cytoskeletal system, the beaded chain filaments (BFs). The BFs had been morphologically identified more than two decades ago, but the precise identity of their subunit molecules remained unknown. Recently, use of recombinant DNA approaches, refined morphological and immunochemical studies and experiments with mutant mice have allowed the molecular dissection of these structures and provided clues about their potential functins. The BFs represent a highly specialized network of intermediate filaments (IFs) juxtaposed to the plasma membrane. They are obligate heteropolymers composed of two lens-specific polypeptides, filensin and phakinin. In this review we discuss the properties, molecular interactions and in situ arrangement of these two proteins, and comment on their potential roles during lens development. 相似文献
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Fotini Gravani Ioanna Papadaki Eleni Antypa Andrianos Nezos Kyriaki Masselou Dimitrios Ioakeimidis Michael Koutsilieris Haralampos M Moutsopoulos Clio P Mavragani 《Arthritis research & therapy》2015,17(1)
IntroductionTo determine the prevalence and clinical/laboratory associations of subclinical atherosclerosis and impaired bone health in primary Sjogren’s syndrome (SS).Methods64 consecutive patients with primary SS, 77 with rheumatoid arthritis (RA) and 60 healthy controls (HC) οf similar age and sex distribution were enrolled. Demographics, clinical/laboratory features, classical risk factors for atherosclerosis and osteoporosis (OP) were recorded. Intima-medial thickness scores (IMT) and carotid/femoral (C/F) plaque formation, as well as bone mineral density (BMD) and fractures were evaluated. Determinants of IMT/BMD levels and the presence of plaque were assessed by univariate and multivariate models. Serum levels of the Wnt signaling mediators Dickkopf-related protein 1(DKK1) and sclerostin were determined in primary SS patients and HC.ResultsIncreased arterial wall thickening (IMT > 0.90 mm) and impaired bone health (defined as OP or osteopenia), were detected in approximately two-thirds of primary SS and RA patients, with a mean IMT value being significantly increased compared to HC. The presence of primary SS emerged as an independent risk factor for arterial wall thickening when traditional risk factors for cardiovascular disease (CVD) including age, sex, hypertension, smoking (pack/years), LDL and HDL levels were taken into account in a multivariate model [adjusted OR 95% (CI): 2.8 (1.04-7.54)]. In primary SS, age was revealed as independent predictor of increased IMT scores; age and lymphopenia as well as increased urine pH as independent determinants of C/F plaque formation and OP/osteopenia, respectively. An independent association of OP/osteopenia with plaque formation was observed when independent predictors for both variables were considered, with low DKK1 levels being associated with both plaque formation and lower BMD levels.ConclusionsComorbidities such as subclinical atherosclerosis and impaired bone health occur frequently in primary SS, in association with disease related features and traditional risk factors. Wnt signaling mediators are potentially involved in the pathogenesis of both entities.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0613-6) contains supplementary material, which is available to authorized users. 相似文献28.
Xaplanteri MA Papadopoulos G Leontiadou F Choli-Papadopoulou T Kalpaxis DL 《Journal of molecular biology》2007,369(2):489-497
In the crystal structure of the 30S ribosomal subunit from Thermus thermophilus, cysteine 24 of ribosomal protein S14 (TthS14) occupies the first position in a CXXC-X12-CXXC motif that coordinates a zinc ion. The structural and functional importance of cysteine 24, which is widely conserved from bacteria to humans, was studied by its replacement with serine and by incorporating the resulting mutant into Escherichia coli ribosomes. The capability of such modified ribosomes in binding tRNA at the P and A-sites was equal to that obtained with ribosomes incorporating wild-type TthS14. In fact, both chimeric ribosomal species exhibited 20% lower tRNA affinity compared with native E. coli ribosomes. In addition, replacement of the native E. coli S14 by wild-type, and particularly by mutant TthS14, resulted in reduced capability of the 30S subunit for association with 50S subunits. Nevertheless, ribosomes from transformed cells sedimented normally and had a full complement of proteins. Unexpectedly, the peptidyl transferase activity in the chimeric ribosomes bearing mutant TthS14 was much lower than that measured in ribosomes incorporating wild-type TthS14. The catalytic center of the ribosome is located within the 50S subunit and, therefore, it is unlikely to be directly affected by changes in the structure of S14. More probably, the perturbing effects of S14 mutation on the catalytic center seem to be propagated by adjacent intersubunit bridges or the P-site tRNA molecule, resulting in weak donor-substrate reactivity. This hypothesis was verified by molecular dynamics simulation analysis. 相似文献
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Elisa Alonso-Perez Marian Suarez-Gestal Manuel Calaza Francisco J Blanco Ana Suarez Maria Jose Santos Chryssa Papasteriades Patricia Carreira Rudolf Pullmann Josep Ordi-Ros Maurizio Marchini Fotini N Skopouli Marc Bijl Nadia Barrizone Gian Domenico Sebastiani Sergio Migliaresi Torsten Witte Bernard R Lauwerys Attila Kovacs Sarka Ruzickova Juan J Gomez-Reino Antonio Gonzalez 《Arthritis research & therapy》2014,16(3):R128
Introduction
We aimed to replicate a recent study which showed higher genetic risk load at 15 loci in men than in women with systemic lupus erythematosus (SLE). This difference was very significant, and it was interpreted as indicating that men require more genetic susceptibility than women to develop SLE.Methods
Nineteen SLE-associated loci (thirteen of which are shared with the previous study) were analyzed in 1,457 SLE patients and 1,728 healthy controls of European ancestry. Genetic risk load was calculated as sex-specific sum genetic risk scores (GRSs).Results
Our results did not replicate those of the previous study at either the level of individual loci or the global level of GRSs. GRSs were larger in women than in men (4.20 ± 1.07 in women vs. 3.27 ± 0.98 in men). This very significant difference (P < 10−16) was more dependent on the six new loci not included in the previous study (59% of the difference) than on the thirteen loci that are shared (the remaining 41%). However, the 13 shared loci also showed a higher genetic risk load in women than in men in our study (P = 6.6 × 10−7), suggesting that heterogeneity of participants, in addition to different loci, contributed to the opposite results.Conclusion
Our results show the lack of a clear trend toward higher genetic risk in one of the sexes for the analyzed SLE loci. They also highlight several limitations of assessments of genetic risk load, including the possibility of ascertainment bias with loci discovered in studies that have included mainly women. 相似文献30.
Katayoun Aghajani Shilpa Keerthivasan Yu Yu Fotini Gounari 《Genesis (New York, N.Y. : 2000)》2012,50(12):908-913
After thymic emigration CD4‐T‐cells continue to differentiate into multiple effector and suppressor sublineages in peripheral lymphoid organs. In vivo analysis of peripheral CD4‐T‐cell differentiation has relied on animal models with targeted gene mutations. These are expressed either constitutively or conditionally after Cre mediated recombination. Available Cre transgenic strains to specifically target T‐cells act at stages of thymocyte development that precede thymic selection. Tracing gene functions in CD4‐T‐cell development after thymic exit becomes complicated when the targeted gene is essential during thymic development. Other approaches to conditionally modify gene functions in peripheral T‐cells involve infection of in vitro activated cells with Cre expressing lenti‐, retro‐, or adenoviruses, which precludes in vivo analyses. To study molecular mechanisms of peripheral CD4‐T‐cell differentiation in vivo and in vitro we generated transgenic mice expressing a tamoxifen inducible Cre recombinase (CreERT2) under the control of the CD4 gene promoter. We show here that in CD4CreERT2 mice Cre is inducibly and selectively activated in CD4‐T‐cells. Tamoxifen treatment both in vivo and in vitro results in efficient recombination of loci marked by LoxP sites. Moreover, this strain shows no abnormalities related to transgene insertion. Therefore it provides a valuable tool for studying gene function during differentiation of naïve peripheral CD4‐T‐cells into effector or suppressor sub‐lineages. genesis 50:908–913, 2012. © 2012 Wiley Periodicals, Inc. 相似文献