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51.
Vincent Daien Isabelle Carriere Ryo Kawasaki Jean-Paul Cristol Max Villain Pierre Fesler Karen Ritchie Cecile Delcourt 《PloS one》2013,8(7)
Purpose
Retinal vascular caliber has been linked with increased cardiovascular risk and is predictive of cardiovascular pathology, including stroke and coronary heart disease. Oxidative stress, as well as inflammatory mechanisms, plays a major role in the pathogenesis and progression of atherosclerosis, plaque rupture and vascular thrombotic propensity. The purpose of this study is to explore the relationship between retinal vascular calibers and biomarkers of oxidative stress and inflammation, in subjects free of cardiovascular pathology.Patients and Methods
Cross-sectional analysis from a community-dwelling cohort comprising 1224 individuals aged 60 years and over, without a history of coronary or peripheral artery disease or stroke. Retinal vascular caliber was measured from fundus photographs using semi-automated standardized imaging software. Oxidative stress was evaluated using plasma superoxide dismutase 2 and glutathione peroxidase (GPx-3) activities, and inflammatory state was assessed using plasma high sensitivity C-reactive protein (hsCRP) and orosomucoid.Results
In a multivariate model controlling for cardiovascular risk factors, larger retinal arteriolar caliber was independently related to higher level of GPx-3 activity (p = 0.003) whereas larger venular caliber was associated with higher levels of hsCRP (p = 0.0001) and orosomucoid (p = 0.01).Conclusion
In the present study, biomarkers of oxidative stress regulation and inflammation were independently associated with retinal vascular calibers. This suggests that an assessment of retinal vessels may offer early and non-invasive detection of subclinical vascular pathology. 相似文献52.
53.
54.
Akira Ainai Elly van Riet Ryo Ito Kazuyuki Ikeda Kyosuke Senchi Tadaki Suzuki Shin-ichi Tamura Hideki Asanuma Takato Odagiri Masato Tashiro Takeshi Kurata Pretty Multihartina Vivi Setiawaty Krisna Nur Andriana Pangesti Hideki Hasegawa 《Microbiology and immunology》2020,64(4):313-325
Intranasally administered influenza vaccines could be more effective than injected vaccines, because intranasal vaccination can induce virus-specific immunoglobulin A (IgA) antibodies in the upper respiratory tract, which is the initial site of infection. In this study, immune responses elicited by an intranasal inactivated vaccine of influenza A(H5N1) virus were evaluated in healthy individuals naive for influenza A(H5N1) virus. Three doses of intranasal inactivated whole-virion H5 influenza vaccine induced strong neutralizing nasal IgA and serum IgG antibodies. In addition, a mucoadhesive excipient, carboxy vinyl polymer, had a notable impact on the induction of nasal IgA antibody responses but not on serum IgG antibody responses. The nasal hemagglutinin (HA)-specific IgA antibody responses clearly correlated with mucosal neutralizing antibody responses, indicating that measurement of nasal HA-specific IgA titers could be used as a surrogate for the mucosal antibody response. Furthermore, increased numbers of plasma cells and vaccine antigen-specific Th cells in the peripheral blood were observed after vaccination, suggesting that peripheral blood biomarkers may also be used to evaluate the intranasal vaccine-induced immune response. However, peripheral blood immune cell responses correlated with neutralizing antibody titers in serum samples but not in nasal wash samples. Thus, analysis of the peripheral blood immune response could be a surrogate for the systemic immune response to intranasal vaccination but not for the mucosal immune response. The current study suggests the clinical potential of intranasal inactivated vaccines against influenza A(H5N1) viruses and highlights the need to develop novel means to evaluate intranasal vaccine-induced mucosal immune responses. 相似文献
55.
Structural characterization of alternatively folded and partially disordered protein conformations remains challenging. Outer surface protein A (OspA) is a pivotal protein in Borrelia infection, which is the etiological agent of Lyme disease. OspA exists in equilibrium with intermediate conformations, in which the central and the C-terminal regions of the protein have lower stabilities than the N-terminal. Here, we characterize pressure- and temperature-stabilized intermediates of OspA by nuclear magnetic resonance spectroscopy combined with paramagnetic relaxation enhancement (PRE). We found that although the C-terminal region of the intermediate was partially disordered, it retains weak specific contact with the N-terminal region, owing to a twist of the central β-sheet and increased flexibility in the polypeptide chain. The disordered C-terminal region of the pressure-stabilized intermediate was more compact than that of the temperature-stabilized form. Further, molecular dynamics simulation demonstrated that temperature-induced disordering of the β-sheet was initiated at the C-terminal region and continued through to the central region. An ensemble of simulation snapshots qualitatively described the PRE data from the intermediate and indicated that the intermediate structures of OspA may expose tick receptor-binding sites more readily than does the basic folded conformation. 相似文献
56.
Georgios A. Pavlopoulos Parveen Kumar Alejandro Sifrim Ryo Sakai Meng Lay Lin Thierry Voet Yves Moreau Jan Aerts 《Nucleic acids research》2013,41(11):e118
The introduction of next generation sequencing methods in genome studies has made it possible to shift research from a gene-centric approach to a genome wide view. Although methods and tools to detect single nucleotide polymorphisms are becoming more mature, methods to identify and visualize structural variation (SV) are still in their infancy. Most genome browsers can only compare a given sequence to a reference genome; therefore, direct comparison of multiple individuals still remains a challenge. Therefore, the implementation of efficient approaches to explore and visualize SVs and directly compare two or more individuals is desirable. In this article, we present a visualization approach that uses space-filling Hilbert curves to explore SVs based on both read-depth and pair-end information. An interactive open-source Java application, called Meander, implements the proposed methodology, and its functionality is demonstrated using two cases. With Meander, users can explore variations at different levels of resolution and simultaneously compare up to four different individuals against a common reference. The application was developed using Java version 1.6 and Processing.org and can be run on any platform. It can be found at http://homes.esat.kuleuven.be/~bioiuser/meander. 相似文献
57.
Widyanto Dwi Nugroho Satoshi Nakaba Yusuke Yamagishi Shahanara Begum Sri Nugroho Marsoem Jae-Heung Ko Hyun-O Jin Ryo Funada 《Annals of botany》2013,112(7):1321-1329
Background and Aims
Gibberellin stimulates negative gravitropism and the formation of tension wood in tilted Acacia mangium seedlings, while inhibitors of gibberellin synthesis strongly inhibit the return to vertical growth and suppress the formation of tension wood. To characterize the role of gibberellin in tension wood formation and gravitropism, this study investigated the role of gibberellin in the development of gelatinous fibres and in the changes in anatomical characteristics of woody elements in Acacia mangium seedlings exposed to a gravitational stimulus.Methods
Gibberellin, paclobutrazol and uniconazole-P were applied to the soil in which seedlings were growing, using distilled water as the control. Three days after the start of treatment, seedlings were inclined at 45 ° to the vertical and samples were harvested 2 months later. The effects of the treatments on wood fibres, vessel elements and ray parenchyma cells were analysed in tension wood in the upper part of inclined stems and in the opposite wood on the lower side of inclined stems.Key Results
Application of paclobutrazol or uniconazole-P inhibited the increase in the thickness of gelatinous layers and prevented the elongation of gelatinous fibres in the tension wood of inclined stems. By contrast, gibberellin stimulated the elongation of these fibres. Application of gibberellin and inhibitors of gibberellin biosynthesis had only minor effects on the anatomical characteristics of vessel and ray parenchyma cells.Conclusions
The results suggest that gibberellin is important for the development of gelatinous fibres in the tension wood of A. mangium seedlings and therefore in gravitropism. 相似文献58.
Nathan P. Coussens Ryo Hayashi Patrick H. Brown Lakshmi Balagopalan Andrea Balbo Itoro Akpan Jon C. D. Houtman Valarie A. Barr Peter Schuck Ettore Appella Lawrence E. Samelson 《Molecular and cellular biology》2013,33(21):4140-4151
The adapter molecules SLP-76 and LAT play central roles in T cell activation by recruiting enzymes and other adapters into multiprotein complexes that coordinate highly regulated signal transduction pathways. While many of the associated proteins have been characterized, less is known concerning the mechanisms of assembly for these dynamic and potentially heterogeneous signaling complexes. Following T cell receptor (TCR) stimulation, SLP-76 is found in structures called microclusters, which contain many signaling complexes. Previous studies showed that a mutation to the SLP-76 C-terminal SH2 domain nearly abolished SLP-76 microclusters, suggesting that the SH2 domain facilitates incorporation of signaling complexes into microclusters. S. C. Bunnell, A. L. Singer, D. I. Hong, B. H. Jacque, M. S. Jordan, M. C. Seminario, V. A. Barr, G. A. Koretzky, and L. E. Samelson, Mol. Cell. Biol., 26:7155–7166, 2006). Using biophysical methods, we demonstrate that the adapter, ADAP, contains three binding sites for SLP-76, and that multipoint binding to ADAP fragments oligomerizes the SLP-76 SH2 domain in vitro. These results were complemented with confocal imaging and functional studies of cells expressing ADAP with various mutations. Our results demonstrate that all three binding sites are critical for SLP-76 microcluster assembly, but any combination of two sites will partially induce microclusters. These data support a model whereby multipoint binding of SLP-76 to ADAP facilitates the assembly of SLP-76 microclusters. This model has implications for the regulation of SLP-76 and LAT microclusters and, as a result, T cell signaling. 相似文献
59.
Many social animals develop vocal communications to send and receive information efficiently in a group. In alarm communication, call recipients in a social group evaluate alarm calls, enhancing their probability of survival in the face of predatory threats. Calls from naïve and younger group members might be less evocative, in terms of rendering group members vigilant, than calls from more experienced adults because adults are generally more reliable. It remains uncertain, however, what acoustic characteristics render an alarm call reliable. Here, we report that adult degus, Octodon degus (Rodentia, Octodontidae), produced an alarm with a frequency-modulated (FM) syllable, accompanied by low bandwidth and entropy, to evoke a high-vigilance response amongst receivers. Unlike adults, subadult degus did not emit the FM syllable in the warning context, and their call without the FM syllable evoked less vigilance than the adult alarm. We suggest that the FM structure of the adult-produced syllable serves as the primary feature characterizing a reliable alarm call. Our results are consistent with those found in other social rodents, e.g., ground squirrels and gerbils, also produce FM alarm calls in high-urgency situations supports the importance of the FM syllable in alarm communication. 相似文献