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113.
Ana-Maria Bliuc Craig McGarty Lisa Hartley Daniela Muntele Hendres 《Ethnic and racial studies》2013,36(12):2174-2194
This research explores the role of opinion-based groups in understanding responses to racist violence such as the 2005 Cronulla riots in Australia. Traditionally, explanations of collective action in social psychology and sociology focus on conflict between broad social categories. We propose that the responses to the riots can be understood not only as inter-group conflict between Muslims and non-Muslims, or an in-group argument amongst non-Muslims, but as a bona fide inter-group conflict between supporters and opponents of the riots. We argue that these groups use rhetoric in attempts to claim dominant status within society by aligning their identities with positively valued social categories such as ethnicities and national identities. The analysis of rhetoric from the groups supporting and opposing the riots demonstrates consistent, albeit contested, attempts to align support for the riot with the Australian national category in conflict with countervailing attempts to align opposition to the riot with the same national category. 相似文献
114.
Sek Yee Tan Bonifacio F. Cayabyab Edwin P. Alcantara Fangneng Huang Kanglai He Kenneth W. Nickerson Blair D. Siegfried 《Journal of invertebrate pathology》2013
The European (Ostrinia nubilalis Hübner) and Asian corn borers (Ostrinia furnacalis Guenée) are closely related and display similar sensitivity to Cry1 toxins. In this study, we compared the binding patterns of Cry1Ab and Cry1F toxins between both Ostrinia spp., as well as the expression of putative cadherin- and aminopeptidase-N (APN)-like protein receptors. Additionally, cDNA sequences of these putative toxin receptors from both Ostrinia species were compared. Ligand blots for both species indicated a similar binding pattern for Cry1Ab with the strongest immunoreactive band at 260 kDa in both species. In addition, similar expression of the putative cadherin- and APN-like protein receptors were observed at 260 and 135 kDa, respectively. A high degree of similarity (98% amino acid sequence identity) of cDNA sequences for both putative receptor sequences was observed. The Cry1F ligand blot revealed that O. furnacalis and O. nubilalis BBMV exhibited slightly different binding patterns, with strong binding to putative proteins at 150 and 140 kDa, respectively. Both proteins appeared to also bind Cry1Ab, although the signal intensity was much reduced with Cry1Ab. O. furnacalis showed an additional but weaker band at 210 kDa relative to the 150 kDa band. Diatraea saccharalis (Fabricius), which was used as an outgroup species, exhibited different binding patterns than either Ostrinia species, with both Cry1Ab and Cry1F toxins binding to a 210 kDa protein. These results support the previous experiments indicating that O. nubilalis and O. furnacalis share similar patterns of susceptibility to Cry toxins. 相似文献
115.
Rachel A. Hill Yee‐Wen Candace Wu Andrea Gogos Maarten van den Buuse 《Journal of neurochemistry》2013,126(3):389-399
Neurodevelopmental psychiatric disorders such as schizophrenia may be caused by a combination of gene × environment, gene × gene, and/or gene × sex interactions. Reduced expression of both Reelin and Brain‐Derived Neurotrophic factor (BDNF) has been associated with schizophrenia in human post‐mortem studies. However, it remains unclear how Reelin and BDNF interact (gene × gene) and whether this is sex‐specific (gene × sex). This study investigated BDNF‐TrkB signaling in the hippocampus of male and female Reelin heterozygous (Rln+/?) mice. We found significantly increased levels of BDNF in the ventral hippocampus (VHP) of female, but not male Rln+/? compared to wild‐type (WT) controls. While levels of TrkB were not significantly altered, phosphorylated TrkB (pTrkB) levels were significantly lower, again only in female Rln+/? compared to WT. This translated to downstream effects with a significant decrease in phosphorylated ERK1 (pERK1). No changes in BDNF, TrkB, pTrkB or pERK1/2 were observed in the dorsal hippocampus of Rln+/? mice. Ovariectomy (OVX) had no effect in WT controls, but caused a significant decrease in BDNF expression in the VHP of Rln+/? mice to the levels of intact WT controls. The high expression of BDNF was restored in OVX Rln+/? mice by 17β‐estradiol treatment, suggesting that Rln+/? mice respond differently to an altered estradiol state than WT controls. In addition, while OVX had no significant effect on TrkB or ERK expression/phosphorylation, OVX + estradiol treatment markedly increased TrkB and ERK1 phosphorylation in Rln+/? and, to a lesser extent in WT controls, compared to intact genotype‐matched controls. These data may provide a better understanding of the interaction of Reelin and BDNF in the hippocampus, which may be involved in schizophrenia. 相似文献
116.
Richard Kin Ting Kam Weili Shi Sun On Chan Yonglong Chen Gang Xu Clara Bik-San Lau Kwok Pui Fung Wood Yee Chan Hui Zhao 《The Journal of biological chemistry》2013,288(44):31477-31487
All-trans-retinoic acid (atRA) is an important morphogen involved in many developmental processes, including neural differentiation, body axis formation, and organogenesis. During early embryonic development, atRA is synthesized from all-trans-retinal (atRAL) in an irreversible reaction mainly catalyzed by retinal dehydrogenase 2 (aldh1a2), whereas atRAL is converted from all-trans-retinol via reversible oxidation by retinol dehydrogenases, members of the short-chain dehydrogenase/reductase family. atRA is degraded by cytochrome P450, family 26 (cyp26). We have previously identified a short-chain dehydrogenase/reductase 3 (dhrs3), which showed differential expression patterns in Xenopus embryos. We show here that the expression of dhrs3 was induced by atRA treatment and overexpression of Xenopus nodal related 1 (xnr1) in animal cap assay. Overexpression of dhrs3 enhanced the phenotype of excessive cyp26a1. In embryos overexpressing aldh1a2 or retinol dehydrogenase 10 (rdh10) in the presence of their respective substrates, Dhrs3 counteracted the action of Aldh1a2 or Rdh10, indicating that retinoic acid signaling is attenuated. Knockdown of Dhrs3 by antisense morpholino oligonucleotides resulted in a phenotype of shortened anteroposterior axis, reduced head structure, and perturbed somitogenesis, which were also found in embryos treated with an excess of atRA. Examination of the expression of brachyury, not, goosecoid, and papc indicated that convergent extension movement was defective in Dhrs3 morphants. Taken together, these studies suggest that dhrs3 participates in atRA metabolism by reducing atRAL levels and is required for proper anteroposterior axis formation, neuroectoderm patterning, and somitogenesis. 相似文献
117.
Justin Lira Jeff Beringer Stephanie Burton Samantha Griffin Joel Sheets Sek Yee Tan Aaron Woosley Sarah Worden Kenneth E. Narva 《Applied and environmental microbiology》2013,79(24):7590-7597
Bacillus thuringiensis is an important source of insect resistance traits in commercial crops. In an effort to prolong B. thuringiensis trait durability, insect resistance management programs often include combinations of insecticidal proteins that are not cross resistant or have demonstrable differences in their site of action as a means to mitigate the development of resistant insect populations. In this report, we describe the activity spectrum of a novel B. thuringiensis Cry protein, Cry1Bh1, against several lepidopteran pests, including laboratory-selected B. thuringiensis-resistant strains of Ostrinia nubilalis and Heliothis virescens and progeny of field-evolved B. thuringiensis-resistant strains of Plutella xylostella and Spodoptera frugiperda. Cry1Bh1 is active against susceptible and B. thuringiensis-resistant colonies of O. nubilalis, P. xylostella, and H. virescens in laboratory diet-based assays, implying a lack of cross-resistance in these insects. However, Cry1Bh1 is not active against susceptible or Cry1F-resistant S. frugiperda. Further, Cry1Bh1 does not compete with Cry1Fa or Cry1Ab for O. nubilalis midgut brush border membrane binding sites. Cry1Bh1-expressing corn, while not completely resistant to insect damage, provided significantly better leaf protection against Cry1Fa-resistant O. nubilalis than did Cry1Fa-expressing hybrid corn. The lack of cross-resistance with Cry1Ab and Cry1Fa along with independent membrane binding sites in O. nubilalis makes Cry1Bh1 a candidate to further optimize for in-plant resistance to this pest. 相似文献
118.
Yee?Him Cheung Tenzin Gayden Philippe?M. Campeau Charles?A. LeDuc Donna Russo Van-Hung Nguyen Jiancheng Guo Ming Qi Yanfang Guan Steffen Albrecht Brenda Moroz Karen?W. Eldin James?T. Lu Jeremy Schwartzentruber David Malkin Albert?M. Berghuis Sherif Emil Richard?A. Gibbs David?L. Burk Megan Vanstone Brendan?H. Lee David Orchard Kym?M. Boycott Wendy?K. Chung Nada Jabado 《American journal of human genetics》2013,92(6):996-1000
Infantile myofibromatosis (IM) is the most common benign fibrous tumor of soft tissues affecting young children. By using whole-exome sequencing, RNA sequencing, and targeted sequencing, we investigated germline and tumor DNA in individuals from four distinct families with the familial form of IM and in five simplex IM cases with no previous family history of this disease. We identified a germline mutation c.1681C>T (p.Arg561Cys) in platelet-derived growth factor receptor β (PDGFRB) in all 11 affected individuals with familial IM, although none of the five individuals with nonfamilial IM had mutations in this gene. We further identified a second heterozygous mutation in PDGFRB in two myofibromas from one of the affected familial cases, indicative of a potential second hit in this gene in the tumor. PDGFR-β promotes growth of mesenchymal cells, including blood vessels and smooth muscles, which are affected in IM. Our findings indicate p.Arg561Cys substitution in PDGFR-β as a cause of the dominant form of this disease. They provide a rationale for further investigations of this specific mutation and gene to assess the benefits of targeted therapies against PDGFR-β in aggressive life-threatening familial forms of the disease. 相似文献
119.
Nafisa-Katrin Seich al Basatena Clive J. Hoggart Lachlan J. Coin Paul F. O’Reilly 《Genetics》2013,193(1):243-253
In recent years it has emerged that structural variants have a substantial impact on genomic variation. Inversion polymorphisms represent a significant class of structural variant, and despite the challenges in their detection, data on inversions in the human genome are increasing rapidly. Statistical methods for inferring parameters such as the recombination rate and the selection coefficient have generally been developed without accounting for the presence of inversions. Here we exploit new software for simulating inversions in population genetic data, invertFREGENE, to assess the potential impact of inversions on such methods. Using data simulated by invertFREGENE, as well as real data from several sources, we test whether large inversions have a disruptive effect on widely applied population genetics methods for inferring recombination rates, for detecting selection, and for controlling for population structure in genome-wide association studies (GWAS). We find that recombination rates estimated by LDhat are biased downward at inversion loci relative to the true contemporary recombination rates at the loci but that recombination hotspots are not falsely inferred at inversion breakpoints as may have been expected. We find that the integrated haplotype score (iHS) method for detecting selection appears robust to the presence of inversions. Finally, we observe a strong bias in the genome-wide results of principal components analysis (PCA), used to control for population structure in GWAS, in the presence of even a single large inversion, confirming the necessity to thin SNPs by linkage disequilibrium at large physical distances to obtain unbiased results. 相似文献