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71.
Fernandez-Rivas M Aalbers M Fötisch K de Heer P Notten S Vieths S van Ree R 《Arbeiten aus dem Paul-Ehrlich-Institut (Bundesamt für Sera und Impfstoffe) zu Frankfurt a.M》2006,(95):84-8; discussion 88-90, 100-4
Immune reactivity is a key issue in the evaluation of the quality of recombinant allergens as potential reference materials. Within the frame of the CREATE project, the immune reactivity of the natural and recombinant versions of the major allergens of birch pollen (Bet v 1), grass pollen (Phl p 1 and 5), olive pollen (Ole e 1), and house dust mite (Der p 1 and 2, and Der f 1 and 2) was analysed. The IgE binding capacity of the allergens was studied by direct RAST and RAST inhibition, and their biological activity by basophil histamine release, using sera of allergic patients selected across Europe. For birch pollen, rBet v 1 is an excellent mimic of the natural allergen. For grass pollen, rPhl p 1 showed a significant lower IgE reactivity and was not considered a suitable candidate, whereas rPhl p 5a exhibited an immune reactivity closer to that of its natural counterpart. For olive, rOle e 1 had a lower IgE binding capacity in RAST but a higher biological activity in histamine release. For house dust mite, recombinant group 1 allergens were significantly less potent than their natural counterparts, but recombinant group 2 allergens were close mimics of their natural homologues. 相似文献
72.
Sensitivity and specificity of human brain glutathione concentrations measured using short‐TE 1H MRS at 7 T 下载免费PDF全文
Dinesh K. Deelchand Małgorzata Marjańska James S. Hodges Melissa Terpstra 《NMR in biomedicine》2016,29(5):600-606
Although the MR editing techniques that have traditionally been used for the measurement of glutathione (GSH) concentrations in vivo address the problem of spectral overlap, they suffer detriments associated with inherently long TEs. The purpose of this study was to characterize the sensitivity and specificity for the quantification of GSH concentrations without editing at short TE. The approach was to measure synthetically generated changes in GSH concentrations from in vivo stimulated echo acquisition mode (STEAM) spectra after in vitro GSH spectra had been added to or subtracted from them. Spectra from five test subjects were synthetically altered to mimic changes in the GSH signal. To account for different background noise between measurements, retest spectra (from the same individuals as used to generate the altered data) and spectra from five other individuals were compared with the synthetically altered spectra to investigate the reliability of the quantification of GSH concentration. Using STEAM spectroscopy at 7 T, GSH concentration differences on the order of 20% were detected between test and retest studies, as well as between differing populations in a small sample (n = 5) with high accuracy (R2 > 0.99) and certainty (p ≤ 0.01). Both increases and decreases in GSH concentration were reliably quantified with small impact on the quantification of ascorbate and γ‐aminobutyric acid. These results show the feasibility of using short‐TE 1H MRS to measure biologically relevant changes and differences in human brain GSH concentration. Although these outcomes are specific to the experimental approach used and the spectral quality achieved, this study serves as a template for the analogous scrutiny of quantification reliability for other compounds, methodologies and spectral qualities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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74.
Hiroko Morisaki Gretchen MacCarrick Mark Lindsay David Liang Sarju G. Mehta Jennifer Hague Judith Verhagen Ingrid van de Laar Marja Wessels Yvonne Detisch Mieke van Haelst Annette Baas Klaske Lichtenbelt Kees Braun Denise van der Linde Jolien Roos‐Hesselink George McGillivray Josephina Meester Isabelle Maystadt Paul Coucke Elie El‐Khoury Sandhya Parkash Birgitte Diness Lotte Risom Ingrid Scurr Yvonne Hilhorst‐Hofstee Takayuki Morisaki Julie Richer Julie Désir Marlies Kempers Andrea L. Rideout Gabrielle Horne Chris Bennett Elisa Rahikkala Geert Vandeweyer Maaike Alaerts Aline Verstraeten Hal Dietz Lut Van Laer Bart Loeys 《Human mutation》2018,39(5):621-634
The Loeys–Dietz syndrome (LDS) is a connective tissue disorder affecting the cardiovascular, skeletal, and ocular system. Most typically, LDS patients present with aortic aneurysms and arterial tortuosity, hypertelorism, and bifid/broad uvula or cleft palate. Initially, mutations in transforming growth factor‐β (TGF‐β) receptors (TGFBR1 and TGFBR2) were described to cause LDS, hereby leading to impaired TGF‐β signaling. More recently, TGF‐β ligands, TGFB2 and TGFB3, as well as intracellular downstream effectors of the TGF‐β pathway, SMAD2 and SMAD3, were shown to be involved in LDS. This emphasizes the role of disturbed TGF‐β signaling in LDS pathogenesis. Since most literature so far has focused on TGFBR1/2, we provide a comprehensive review on the known and some novel TGFB2/3 and SMAD2/3 mutations. For TGFB2 and SMAD3, the clinical manifestations, both of the patients previously described in the literature and our newly reported patients, are summarized in detail. This clearly indicates that LDS concerns a disorder with a broad phenotypical spectrum that is still emerging as more patients will be identified. All mutations described here are present in the corresponding Leiden Open Variant Database. 相似文献
75.
Anne S. Koponen Juha E. Peltonen Marja K. Päivinen Jyrki M. Aho Harriet J. Hägglund Arja L. Uusitalo Harri J. Lindholm Heikki O. Tikkanen 《European journal of applied physiology》2013,113(5):1181-1188
Blood O2 carrying capacity affects aerobic capacity (VO2max). Patients with type 1 diabetes have a risk for anaemia along with renal impairment, and they often have low VO2max. We investigated whether total haemoglobin mass (tHb-mass) and blood volume (BV) differ in men with type 1 diabetes (T1D, n = 12) presently without complications and in healthy men (CON, n = 23) (age-, anthropometry-, physical activity-matched), to seek an explanation for low VO2max. We determined tHb-mass, BV, haemoglobin concentration ([Hb]), and VO2max in T1D and CON. With similar (mean ± SD) [Hb] (144 vs. 145 g l?1), T1D had lower tHb-mass (10.1 ± 1.4 vs. 11.0 ± 1.1 g kg?1, P < 0.05), BV (76.8 ± 9.5 vs. 83.5 ± 8.3 ml kg?1, P < 0.05) and VO2max (35.4 ± 4.8 vs. 44.9 ± 7.5 ml kg?1 min?1, P < 0.001) than CON. VO2max correlated with tHb-mass and BV both in T1D (r = 0.71, P < 0.01 and 0.67, P < 0.05, respectively) and CON (r = 0.54, P < 0.01 and 0.66, P < 0.001, respectively), but not with [Hb]. Linear regression slopes were shallower in T1D than CON both between VO2max and tHb-mass (2.4 and 3.6 ml kg?1 min?1 vs. g kg?1, respectively) and VO2max and BV (0.3 and 0.6 ml kg?1 min?1 vs. g kg?1, respectively), indicating that T1D were unable to reach similar VO2max than CON at a given tHb-mass and BV. In conclusion, low tHb-mass and BV partly explained low VO2max in T1D and may provide early and more sensitive markers of blood O2 carrying capacity than [Hb] alone. 相似文献
76.
Sung-Ho Huh Katja N?rhi P?ivi H. Lindfors Otso H??r? Lu Yang David M. Ornitz Marja L. Mikkola 《Genes & development》2013,27(4):450-458
In hair follicle development, a placode-derived signal is believed to induce formation of the dermal condensation, an essential component of ectodermal organs. However, the identity of this signal is unknown. Furthermore, although induction and patterning of hair follicles are intimately linked, it is not known whether the mesenchymal condensation is necessary for inducing the initial epithelial pattern. Here, we show that fibroblast growth factor 20 (Fgf20) is expressed in hair placodes and is induced by and functions downstream from epithelial ectodysplasin (Eda)/Edar and Wnt/β-Catenin signaling to initiate formation of the underlying dermal condensation. Fgf20 governs formation of primary and secondary dermal condensations in developing hair follicles and subsequent formation of guard, awl, and auchene hairs. Although primary dermal condensations are absent in Fgf20 mutant mice, a regular array of hair placodes is formed, demonstrating that the epithelial patterning process is independent of known histological and molecular markers of underlying mesenchymal patterns during the initial stages of hair follicle development. 相似文献
77.
Thomas Zeiler MD Antti Taivainen MD PhD Marja Rytkönen PhD Jaakko Rautiainen MSc Henry Karjalainen PhD Rauno Mäntjärvi MD PhD Leena Tuomisto MD PhD Tuomas Virtanen MD PhD 《The Journal of allergy and clinical immunology》1997,100(6):721-727
Background: Lately, renewed interest has arisen in the new forms of allergen immunotherapy because they may offer alternatives for drug treatment. Objective: The purpose of this study was to develop a well-characterized preparation of the main respiratory cow dander allergen, Bos d 2, with attenuated allergenic activity. Methods: The immunologic characteristics of Bos d 2 preparations were studied by indirect IgE ELISA, ELISA inhibition, Western blotting, histamine release, skin prick tests, and the proliferation tests of allergen-specific T-cell clones. Results: The complete recombinant Bos d 2 was observed to bind effectively, IgE of cow-allergic patients in indirect ELISA. In other experiments, the IgE-binding capacity of recombinant Bos d 2 proved to be lower compared with native Bos d 2. When the two overlapping recombinant fragments of Bos d 2 (corresponding amino acids 1-131 and 81-172, respectively) covering the whole molecule were compared with the complete recombinant Bos d 2 with several methods, only a low level of residual reactivity was observed. For example, recombinant fragments could not bind antibody at all in ELISA inhibition tests retaining, however, some reactivity in skin prick tests. In contrast, the fragments were able to stimulate vigorously Bos d 2-specific T-cell clones. Conclusion: The approach we have taken may offer a simple and reproducible way to produce hypoallergenic preparations for immunotherapy, circumventing simultaneously some of the problems of other experimental methods such as individual T-cell epitope recognition in peptide-based immunotherapy. (J Allergy Clin Immunol 1997;100:721-7.) 相似文献
78.
79.
Kinnunen T Buhot C Närvänen A Rytkönen-Nissinen M Saarelainen S Pouvelle-Moratille S Rautiainen J Taivainen A Maillère B Mäntyjärvi R Virtanen T 《European journal of immunology》2003,33(6):1717-1726
We have proposed earlier that the poor capacity of the lipocalin allergen Bos d 2 to stimulate highly allergic subjects' peripheral blood mononuclear cells could be ascribed to endogenous lipocalins and could be related to the allergenic potential of the molecule. Here, we have characterized the proliferative and cytokine responses of human T cell clones against the immunodominant epitope of Bos d 2. We observed, for clone F1-9, that a substitution of aspartic acid for asparagine in the core region of the epitope increased the stimulatory capacity of the peptide about 100-fold in comparison with the natural peptide. For clone K3-2, from a different patient, the substitution of lysine for glutamine or isoleucine for leucine in the core region resulted in about 30-fold and 10-fold increases in the stimulatory capacity of the peptides, respectively. The clones also recognized self-protein-derived peptides but not the peptides derived from other lipocalins. We suggest that the poor recognition of the immunodominant epitope of Bos d 2 can be a factor accounting for Bos d 2-allergic subjects' weak cellular responses. Suboptimal recognition of self and allergen epitopes by T cells may be of significance for the allergenicity of proteins. 相似文献
80.
Noncompaction of the ventricular myocardium is associated with de novo mutation in the beta-myosin heavy chain gene
Budde et al. (2007)
PLoS ONE 2: e1362
Homozygosity for a novel splice site mutation in the cardiac myosin-binding protein C gene causes severe neonatal hypertrophic cardiomyopathy
Xin et al. (2007)
Am J Med Genet 143: 2662–2667
Alpha-cardiac actin mutations produce atrial septal defects
Matsson et al. (2008)
Hum Mol Genet 17: 256–265 相似文献
Budde et al. (2007)
PLoS ONE 2: e1362
Homozygosity for a novel splice site mutation in the cardiac myosin-binding protein C gene causes severe neonatal hypertrophic cardiomyopathy
Xin et al. (2007)
Am J Med Genet 143: 2662–2667
Alpha-cardiac actin mutations produce atrial septal defects
Matsson et al. (2008)
Hum Mol Genet 17: 256–265 相似文献