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The genus Avena L. (Poaceae: Aveneae)) with approximately 30 species forming a distinct polyploid series ranging from diploid through tetraploid to hexaploid with a basic chromosome number of seven (Rajhathy and Thomas 1974; Baum ...
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The genus Avena L. (Poaceae: Aveneae)) with approximately 30 species forming a distinct polyploid series ranging from diploid through tetraploid to hexaploid with a basic chromosome number of seven (Rajhathy and Thomas 1974; Baum 1977; Thomas 1992; Leggett and Thomas 1995; Katsiotis et al. 2000). All Avena species, with the exception of A. macrostachya, are self-pollinated annuals, whereas A. macrostachya is a cross-pollinating, quadrivalent-forming, autotetraploid perennial (Malzew 1930; Baum 1968, 1974; Baum and Rajhathy 1976; Rodionova et al. 1994; Katsiotis et al. 1997). Genome differentiation was initially based on cytological studies of interspecific hybrids and descriptions of species karyotypes (Rajhathy and Thomas 1974; Thomas 1992; Rodionova et al. 1994; Leggett and Markhand 1995). Diploid species have either the A or C genome, tetraploids have either the AB or AC genome and the hexaploids have the ACD genome designation.Although there is considerable morphological, biochemical, geographical, cytotaxonomic and molecular evidence available, much is still unknown about the evolution of the genus. Despite numerous observations made by morphological and cytological studies (Rajhathy et al. 1966; Rajhathy and Thomas 1974; Baum 1977; Linares et al. 1992; Thomas 1992; Leggett and Thomas 1995), the application of different molecular techniques has provided further information on Avena genome relationships, such as in situ hybridization (Chen and Armstrong 1994; Jellen et al. 1994a; Katsiotis et al. 1996; Linares et al. 1998; Irigoyen et al. 2001), the use of molecular markers (Sanchez de la Hoz and Fominaya 1989; Alicchio et al. 1995; O'Donoughue et al. 1995; Ronald et al. 1997; Kianian et al. 1999; Nocelli et al. 1999; Li et al. 2000a, 2000b, 2009; Loskutov and Perchuk 2000; Drossou et al. 2004; Fu and Williams 2008) and the comparison of nucleotide sequences (Cheng et al. 2003; Rodionov et al. 2005; Irigoyen et al. 2006; Nikoloudakis and Katsiotis 2008; Nikoloudakis et al. 2008; Peng et al. 2008). At the diploid level, hybridization among the A and C genome species rarely produces interspecific hybrids, indicating major genomic differences among these species (Fominaya et al. 1988a; Linares et al. 1992; Jellen et al. 1993; Drossou et al. 2004). Although some studies have dealt with phylogenetic relationships among species of different ploidy (Fominaya et al. 1988b; Fabijanski et al. 1990; Gupta et al. 1992; Alicchio et al. 1995; Drossou et al. 2004; Irigoyen et al. 2006; Nikoloudakis et al. 2008), the putative diploid donors of Avena polyploids remain uncertain, especially for the B genome origin in the AB tetraploids and the D genome donor of the ACD hexaploids. There is now good evidence of the close relationships among the A and D genomes (Chen and Armstrong 1994; Jellen et al. 1994a, Leggett and Markhand 1995; Linares et al. 1996, 1998; Loskutov 2008), and the A and B genomes (Leggett and Markhand 1995; Katsiotis et al. 1997). Molecular probes differentiated the D genome (Linares et al. 1998; Peng et al. 2008) and the B genome (Irigoyen et al. 2001; Peng et al. 2008) from the A genome. Using various molecular techniques, A. strigosa (Chen and Armstrong 1994; Jellen et al. 1994a; Leggett and Markhand 1995; Linares et al. 1996), A. canariensis (Li et al. 2000b; Loskutov 2008), A. weistii (Li et al. 2000b; Fu and Williams 2008) and A. longiglumis (Rodionov et al. 2005; Nikoloudakis et al. 2008) had been suggested as the A genome donor of the tetraploid and hexaploid. All of the diploid C genome species have been proposed as the putative donors of the C genome in the hexaploids (Rajhathy and Thomas 1974; Chen and Armstrong 1994; Jellen et al. 1994b; Cheng et al. 2003; Nikoloudakis and Katsiotis 2008).Molecular phylogenetic studies have successfully revealed the origins and evolutionary history of polyploids in plants, clarified the nature of different polyploids and identified their parental lineages and the hybridization
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A novel approach is proposed to solve reliability-based optimization (RBO) problems where the uncertainty dimension can be large and where there may be many reliability constraints. The basic idea is to transform all reliability c...
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A novel approach is proposed to solve reliability-based optimization (RBO) problems where the uncertainty dimension can be large and where there may be many reliability constraints. The basic idea is to transform all reliability constraints in the target RBO problem into non-probabilistic ordinary ones by a pilot analysis. It will be shown that such a pilot analysis only requires a single run of the modified subset simulation (called the parallel subset simulation) regardless the number of the reliability constraints. Once the reliability constraints are approximated by the ordinary ones, the RBO problem can be solved as if it is an ordinary optimization problem. The resulting optimal solution should be approximately feasible, and the corresponding objective function value is minimized under the approximate constraints. Three numerical examples are investigated to verify the proposed novel approach. The results show that the approach may be capable of finding approximate solutions that are usually close to the actual solution of the target RBO problem.
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Tert-butyldiphenylsilyl (TBDPS) was found to be an effective orthogonal protecting strategy for the 5-substituted hydroxyl groups of de novo synthesized deoxyuridine analogues 1-3 and 7-(3-hydroxypropynyl)- of 8-aza-7-deazadeoxyad...
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Tert-butyldiphenylsilyl (TBDPS) was found to be an effective orthogonal protecting strategy for the 5-substituted hydroxyl groups of de novo synthesized deoxyuridine analogues 1-3 and 7-(3-hydroxypropynyl)- of 8-aza-7-deazadeoxyadenosine 4 for their incorporation into oligodeoxynucleotides by phosphoramidite chemistry. It could be completely cleaved under normal and ultra-mild deprotection conditions applied to DNA synthesis, without extra cleaving operation. The new phosphoramidites were coupled as usual with high yields. The new modified oligodeoxynucleotides were characterized by MALDI-TOF and enzymatic cleavage analysis. The thermal stability and conformation of these hydroxyl-functionalized DNA duplexes were evaluated.
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Recently, the increasing number of bio-safety assessments on cadmium-containing quantum dots (QDs) suggested that they could lead to detrimental effects on the central nervous system (CNS) of living organisms, but the underlying a...
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Recently, the increasing number of bio-safety assessments on cadmium-containing quantum dots (QDs) suggested that they could lead to detrimental effects on the central nervous system (CNS) of living organisms, but the underlying action mechanisms are still rarely reported. In this study, whole-transcriptome sequencing was performed to analyze the changes in genome-wide gene expression pattern of rat hippocampus after treatments of cadmium telluride (CdTe) QDs with two sizes to understand better the mechanisms of CdTe QDs causing toxic effects in the CNS. We identified 2095 differentially expressed genes (DEGs). Fifty-five DEGs were between the control and 2.2 nm CdTe QDs, 1180 were between the control and 3.5 nm CdTe QDs and 860 were between the two kinds of CdTe QDs. It seemed that the 3.5 nm CdTe QD exposure might elicit severe effects in the rat hippocampus than 2.2 nm CdTe QDs at the transcriptome level. After bioinformatics analysis, we found that most DEG-enriched Gene Ontology subcategories and Kyoto Encyclopedia of Genes and Genomes pathways were related with the immune system process. For example, the Gene Ontology subcategories included immune response, inflammatory response and T-cell proliferation; Kyoto Encyclopedia of Genes and Genomes pathways included NOD/Toll-like receptor signaling pathway, nuclear factor-κB signaling pathway, tumor necrosis factor signaling pathway, natural killer cell-mediated cytotoxicity and T/B-cell receptor signaling pathway. The traditional toxicological examinations confirmed the systemic immune response and CNS inflammation in rats exposed to CdTe QDs. This transcriptome analysis not only revealed the probably molecular mechanisms of CdTe QDs causing neurotoxicity, but also provided references for the further related studies. Copyright ? 2018 John Wiley & Sons, Ltd.
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Upregulation of mitochondrial function and oxidative metabolism is a hallmark in the differentiation of stem cells. However, the mechanism underlying the metabolic reprogramming and upregulation of mitochondrial function during th...
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Upregulation of mitochondrial function and oxidative metabolism is a hallmark in the differentiation of stem cells. However, the mechanism underlying the metabolic reprogramming and upregulation of mitochondrial function during the differentiation of human mesenchymal stem cells (hMSCs) is largely unclear. Sirt3 has emerged as a sensor in regulating mitochondrial function and antioxidant defence system in cellular response to energy demand or environmental stimuli, but its roles in stem cell differentiation have not been fully understood. In this study, we used adipose-derived hMSCs (ad-hMSCs) to investigate the role of Sirt3 in adipogenic differentiation and in the function of mature adipocytes. We showed that at the early stage of adipogenic differentiation, Sirt3 upregulation is essential for the activation of biogenesis and bioenergetic function of mitochondria. In addition, we found that induction of Forkhead Box O 3a (FoxO3a), an upstream factor that regulates MnSOD gene transcription, is involved in the upregulation of antioxidant enzymes at the early stage of adipogenic differentiation. Silencing of Sirt3 by shRNA decreased the protein level of FoxO3a and subsequently downregulated a number of FoxO3a-mediated antioxidant enzymes and increased oxidative stress in ad-hMSCs after adipogenic induction. Importantly, depletion of Sirt3 compromised the ability of ad-hMSCs to undergo adipogenic differentiation and led to adipocyte dysfunction and insulin resistance. These findings suggest that Sirt3-mediated protein deacetylation plays an important role in regulating oxidative metabolism and antioxidant defence in stem cell differentiation, and that Sirt3 deficiency may be related to insulin resistance. ?2018, ?2018 Informa UK Limited, trading as Taylor & Francis Group.
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The craniofacial skeleton is a complex and unique structure. The perturbation of its development can lead to craniofacial dysmorphology and associated morbidities. Our ability to prevent or mitigate craniofacial skeletal anomalies...
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The craniofacial skeleton is a complex and unique structure. The perturbation of its development can lead to craniofacial dysmorphology and associated morbidities. Our ability to prevent or mitigate craniofacial skeletal anomalies is at least partly dependent on our understanding of the unique physiological development of the craniofacial skeleton. Mouse models are critical tools for the study of craniofacial developmental abnormalities. However, there is a lack of detailed normative data of mouse craniofacial skeletal development in the literature. In this report, we employed high-resolution micro-computed tomography (μCT) in combination with morphometric measurements to analyze the postnatal craniofacial skeletal development from day 7 (P7) through day 390 (P390) of female C57BL/6NCrl mice, a widely used mouse strain. Our data demonstrates a unique craniofacial skeletal development pattern in female C57BL/6NCrl mice, and differentiates the early vs. late craniofacial growth patterns. Additionally, our data documents the complex and differential changes in bone parameters (thickness, bone volume, bone volume/tissue volume, bone mineral density, and tissue mineral density) of various craniofacial bones with different embryonic origins and ossification mechanisms during postnatal growth, which underscores the complexity of craniofacial bone development and provides a reference standard for future quantitative analysis of craniofacial bones.
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The propagation behaviour of Love wave in an initially stressed functionally graded magnetic-electric-elastic half-space carrying a homogeneous layer is investigated. The material parameters in the substrate are assumed to vary ex...
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The propagation behaviour of Love wave in an initially stressed functionally graded magnetic-electric-elastic half-space carrying a homogeneous layer is investigated. The material parameters in the substrate are assumed to vary exponentially along the thickness direction only. The velocity equations of Love wave are derived on the electrically or magnetically open circuit and short circuit boundary conditions, based on the equations of motion of the graded magnetic-electric-elastic mate- rial with the initial stresses and the free traction boundary conditions of surface and the continuous boundary conditions of interface. The dispersive curves are obtained numerically and the influences of the initial stresses and the material gradient index on the dispersive curves are dis- cussed. The investigation provides a basis for the development of new functionally graded magneto-electro-elastic surface wave devices.
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Selectively depleting the pathogenic T cells is a fundamental strategy for the treatment of allograft rejection and autoimmune disease since it retains the overall immune function of host. The concept of killer artificial antigen-...
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Selectively depleting the pathogenic T cells is a fundamental strategy for the treatment of allograft rejection and autoimmune disease since it retains the overall immune function of host. The concept of killer artificial antigen-presenting cells (KaAPCs) has been developed by co-coupling peptide–major histocompatibility complex (pMHC) multimer and anti-Fas monoclonal antibody (mAb) onto the polymeric microparticles (MPs) to induce the apoptosis of antigen-specific T cells. But little information is available about its in vivo therapeutic potential and mechanism. In this study, polyethylenimine (PEI)-coated poly lactic-co-glycolic acid microparticle (PLGA MP) was fabricated as a cell-sized scaffold to covalently co-couple H-2Kb-Ig dimer and anti-Fas mAb for the generation of alloantigen-presenting and apoptosis-inducing MPs. Intravenous infusions of the biodegradable KaAPCs prolonged the alloskin graft survival for 43 days in a single MHC-mismatched murine model, depleted the most of H-2Kb-alloreactive CD8+ T cells in peripheral blood, spleen, and alloskin graft in an antigen-specific manner and anti-Fas-dependent fashion. The cell-sized KaAPCs circulated throughout vasculature into liver, kidney, spleen, lymph nodes, lung, and heart, but few ones into local allograft at early stage, with a retention time up to 36 h in vivo. They colocalized with CD8+ T cells in secondary lymphoid organs while few ones contacted with CD4+ T cells, B cells, macrophage, and dendritic cells, or internalized by phagocytes. Importantly, the KaAPC treatment did not significantly impair the native T cell repertoire or non-pathogenic immune cells, did not obviously suppress the overall immune function of host, and did not lead to visible organ toxicity. Our results strongly document the high potential of PLGA MP-based KaAPCs as a novel antigen-specific immunotherapy for allograft rejection and autoimmune disorder. The in vivo mechanism of alloinhibition, tissue distribution, and biosafety were also initially characterized, which will facilitate its translational studies from bench to bedside.
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Malignant astrocytoma is the most commonly occurring brain tumour in humans. Oxidative stress is implicated in the development of cancers. Superoxide dismutase 2 (SOD2) was found to exert tumour suppressive effect in basic researc...
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Malignant astrocytoma is the most commonly occurring brain tumour in humans. Oxidative stress is implicated in the development of cancers. Superoxide dismutase 2 (SOD2) was found to exert tumour suppressive effect in basic research, but increased SOD2 protein level was associated with higher aggressiveness of human astrocytomas. However, studies reporting alterations of antioxidant enzymes in human astrocytomas often employed less accurate methods or included different types of tumours. Here we analysed the mRNA levels, activities, and protein levels of primary antioxidant enzymes in control brain tissues and various grades of astrocytomas obtained from 40 patients. SOD1 expression, SOD1 activity, and SOD1 protein level were lower in Grade IV astrocytomas. SOD2 expression was lower in low-grade (Grades I and II) and Grade III astrocytomas than in controls, but SOD2 expression and SOD2 protein level were higher in Grade IV astrocytomas than in Grade III astrocytomas. Although there was no change in SOD2 activity and a lower activity of citrate synthase (CS), the MnSOD:CS ratio increased in Grade IV astrocytomas compared with controls and low-grade astrocytomas. Furthermore, SOD1 activity, CS activity, SOD1 expression, GPX4 expression, and GPX4 protein level were inversely correlated with the malignancy, whereas catalase activity, catalase protein, SOD2 protein level, and the SOD2:CS ratio were positively correlated with the degree of malignancy. Lower SOD2:CS ratio was associated with poor outcomes for Grade IV astrocytomas. This is the first study to quantify changes of various primary antioxidant enzymes in different grades of astrocytomas at different levels concurrently in human astrocytomas. ?2018, ?2018 Informa UK Limited, trading as Taylor & Francis Group.
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Although depression-induced altered pain perception has been described in several laboratory and clinical studies, its neurobiological mechanism in the central nervous system (CNS), particularly in the spinal dorsal horn, remains ...
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Although depression-induced altered pain perception has been described in several laboratory and clinical studies, its neurobiological mechanism in the central nervous system (CNS), particularly in the spinal dorsal horn, remains unclear. Therefore, in this study, we aimed to clarify whether nociceptive sensitivity of neuropathic pain is altered in the olfactory bulbectomy (OB) model of depression and whether glucocorticoid receptor (GR), which is involved in the etio-pathologic mechanisms of both major depression and neuropathic pain, contributes to these processes in the spinal dorsal horn of male Sprague-Dawley rats. The results showed that mechanical allodynia and thermal hyperalgesia induced by spinal nerve ligation (SNL) were attenuated in OB-SNL rats with decreased spinal GR expression and nuclear translocation, whereas non-olfactory bulbectomy (NOB)-SNL rats showed increased spinal GR nuclear translocation. In addition, decreased GR nuclear translocation with normal mechanical nociception and hypoalgesia of thermal nociception were observed in OB-Sham rats. Intrathecal injection (i.t.) of GR agonist dexamethasone (Dex; 4 μg/rat/day for 1 week) eliminated the attenuating effect of depression on nociceptive hypersensitivity in OB-SNL rats and aggravated neuropathic pain in NOB-SNL rats, which was associated with the up-regulation of brain-derived neurotrophic factor (BDNF), TrkB and NR2B expression in the spinal dorsal horn. The present study shows that depression attenuates the mechanical allodynia and thermal hyperalgesia of neuropathic pain and suggests that altered spinal GR-BDNF-TrkB signaling may be one of the reasons for depression-induced hypoalgesia.
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