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211.
Laura Martin-Fernandez Andrey Ziyatdinov Marina Carrasco Juan Antonio Millon Angel Martinez-Perez Noelia Vilalta Helena Brunel Montserrat Font Anders Hamsten Juan Carlos Souto José Manuel Soria 《PloS one》2016,11(1)
Background
Venous thromboembolism (VTE) is a common disease where known genetic risk factors explain only a small portion of the genetic variance. Then, the analysis of intermediate phenotypes, such as thrombin generation assay, can be used to identify novel genetic risk factors that contribute to VTE.Objectives
To investigate the genetic basis of distinct quantitative phenotypes of thrombin generation and its relationship to the risk of VTE.Patients/Methods
Lag time, thrombin peak and endogenous thrombin potential (ETP) were measured in the families of the Genetic Analysis of Idiopathic Thrombophilia 2 (GAIT-2) Project. This sample consisted of 935 individuals in 35 extended families selected through a proband with idiopathic thrombophilia. We performed also genome wide association studies (GWAS) with thrombin generation phenotypes.Results
The results showed that 67% of the variation in the risk of VTE is attributable to genetic factors. The heritabilities of lag time, thrombin peak and ETP were 49%, 54% and 52%, respectively. More importantly, we demonstrated also the existence of positive genetic correlations between thrombin peak or ETP and the risk of VTE. Moreover, the major genetic determinant of thrombin generation was the F2 gene. However, other suggestive signals were observed.Conclusions
The thrombin generation phenotypes are strongly genetically determined. The thrombin peak and ETP are significantly genetically correlated with the risk of VTE. In addition, F2 was identified as a major determinant of thrombin generation. We reported suggestive signals that might increase our knowledge to explain the variability of this important phenotype. Validation and functional studies are required to confirm GWAS results. 相似文献212.
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Pascal Mège Anders Ödeen Marc Théry Damien Picard Jean Secondi 《Evolutionary biology》2016,43(1):109-118
Ultraviolet (UV) vision exists in several animal groups. Intuitively, one would expect this trait to be favoured in species living in bright environments, where UV light is the most present. However, UV sensitivity, as deduced from sequences of UV photoreceptors and/or ocular media transmittance, is also present in nocturnal species, raising questions about the selective pressure maintaining this perceptual ability. Amphibians are among the most nocturnal vertebrates but their visual ecology remains poorly understood relative to other groups. Perhaps because many of these species breed in environments that filter out a large part of UV radiation, physiological and behavioural studies of UV sensitivity in this group are scarce. We investigated the extent of UV vision in Caudata, the order of amphibians with the most nocturnal habits. We could recover sequences of the UV sensitive SWS1 opsin in 40 out of 58 species, belonging to 6 families. In all of these species, the evidence suggests the presence of functional SWS1 opsins under purifying selection, potentially allowing UV vision. Interestingly, most species whose opsin genes failed to amplify exhibited particular ecological features that could drive the loss of UV vision. This likely wide distribution of functional UV photoreceptors in Caudata sheds a new light on the visual ecology of amphibians and questions the function of UV vision in nocturnal animal species. 相似文献
216.
Zan Strabac Toril Aalberg Anders Todal Jenssen Marko Valenta 《Ethnic and racial studies》2016,39(15):2665-2682
Immigrant women are a particularly vulnerable part of the immigrant population. In this paper we analyse negative attitudes towards immigrant women in Norway. We focus on immigrant women’s formal job qualifications, their religious background and wearing of hijab – the headscarf sometimes used by Muslim women. Using survey-embedded experiments we are able to analyse the net effects on attitudes of job qualifications, Islamic religious background and the hijab. The results show that native population frequently has more negative views of Muslim women who wear a hijab. The negative effects of a hijab do not seem to be strongly reduced if a woman wearing it has higher education. With a single exception, the results also show that Muslim background in itself (i.e. without the hijab) does not have any strong effect on attitudes of the native population towards immigrant women. 相似文献
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Algal Turbidity Hampers Ornament Perception,but Not Expression,in a Sex‐Role‐Reversed Pipefish 下载免费PDF全文
Josefin Sundin Gunilla Rosenqvist Siri Myhren Anders Berglund 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(3):215-225
Sexual ornaments are used both in intra‐ and intersexual contexts, and these signals have evolved to function in the particular habitat the animal is adapted to. Habitat characteristics may, however, change rapidly due to anthropogenic effects, sometimes at rates too fast for many organisms to adaptively respond. In aquatic ecosystems, eutrophication is currently changing chemical as well as visual properties of the environment. Algae blooms increase water turbidity, and the reduction of water transparency thus has the potential to alter visual ornaments and their perception. However, results are not congruent. Rather, algae turbidity may decrease, increase, or leave ornaments unaffected. The effect seems to depend on exposure time, condition, population and species. Here, we found that the perception of sexual signals, but not their expression, was hampered by turbidity in the sex‐role‐reversed pipefish Nerophis ophidion. In a laboratory experiment we found that female sexual ornaments (i.e., blue color markings and a skinfold) and fecundity was unaffected by turbidity. Male adaptive mate choice for larger females with large ornament was, however, hampered under turbid conditions, whereas in clear water males choose larger, more ornamented females. Thus, we show that water turbidity had no effect on signal expression but did hamper ornament perception and consequently randomized mate choice. 相似文献
219.
Flesh‐eating Streptococcus pyogenes triggers the expression of receptor activator of nuclear factor‐κB ligand 下载免费PDF全文
Hidenori Matsui Yuriko Nakatani Haruno Yoshida Asako Takizawa Osamu Takeuchi Anders Øverby Takashi Takahashi Somay Y. Murayama Koichi Matsuo 《Cellular microbiology》2016,18(10):1390-1404
Human CD46 is a receptor for the M protein of group A streptococcus (GAS). The emm1 GAS strain GAS472 was isolated from a patient suffering from streptococcal toxic shock‐like syndrome. Human CD46‐expressing transgenic (Tg) mice developed necrotizing fasciitis associated with osteoclast‐mediated progressive and severe bone destruction in the hind paws 3 days after subcutaneous infection with 5 × 105 colony‐forming units of GAS472. GAS472 infection induced expression of the receptor activator of nuclear factor‐κB ligand (RANKL) while concomitantly reducing osteoprotegerin expression in the hind limb bones of CD46 Tg mice. Micro‐computed tomography analysis of the bones suggested that GAS472 infection induced local bone erosion and systemic bone loss in CD46 Tg mice. Because treatment with monoclonal antibodies (mAbs) against mouse CD4+ and CD8+ T lymphocytes did not inhibit osteoclastogenesis, T lymphocyte‐derived RANKL was not considered a major contributor to massive bone loss during GAS472 infection. However, immunohistochemical analysis of the hind limb bones showed that GAS472 infection stimulated RANKL production in various bone marrow cells, including fibroblast‐like cells. Treatment with a mAb against mouse RANKL significantly inhibited osteoclast formation and bone resorption. These data suggest that increased expression of RANKL in heterogeneous bone marrow cells provoked bone destruction during GAS infection. 相似文献
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