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Find video protocols related to scientific articles indexed in Pubmed.
Scalable graphene synthesised by plasma-assisted selective reaction on silicon carbide for device applications.
Nanoscale
PUBLISHED: 10-14-2014
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Graphene, a two-dimensional material with honeycomb arrays of carbon atoms, has shown outstanding physical properties that make it a promising candidate material for a variety of electronic applications. To date, several issues related to the material synthesis and device fabrication need to be overcome. Despite the fact that large-area graphene films synthesised by chemical vapour deposition (CVD) can be grown with relatively few defects, the required transfer process creates wrinkles and polymer residues that greatly reduce its performance in device applications. Graphene synthesised on silicon carbide (SiC) has shown outstanding mobility and has been successfully used to develop ultra-high frequency transistors; however, this fabrication method is limited due to the use of costly ultra-high vacuum (UHV) equipment that can reach temperatures over 1500 °C. Here, we show a simple and novel approach to synthesise graphene on SiC substrates that greatly reduces the temperature and vacuum requirements and allows the use of equipment commonly used in the semiconductor processing industry. In this work, we used plasma treatment followed by annealing in order to obtain large-scale graphene films from bulk SiC. After exposure to N2 plasma, the annealing process promotes the reaction of nitrogen ions with Si and the simultaneous condensation of C on the surface of SiC. Eventually, a uniform, large-scale, n-type graphene film with remarkable transport behaviour on the SiC wafer is achieved. Furthermore, graphene field effect transistors (FETs) with high carrier mobilities on SiC were also demonstrated in this study.
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Adaptive divergence with gene flow in incipient speciation of Miscanthus floridulus/sinensis complex (Poaceae).
Plant J.
PUBLISHED: 04-14-2014
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Young incipient species provide ideal materials for untangling the process of ecological speciation in the presence of gene flow. The Miscanthus floridulus/sinensis complex exhibits diverse phenotypic and ecological differences despite recent divergence (approximately 1.59 million years ago). To elucidate the process of genetic differentiation during early stages of ecological speciation, we analyzed genomic divergence in the Miscanthus complex using 72 randomly selected genes from a newly assembled transcriptome. In this study, rampant gene flow was detected between species, estimated as M = 3.36 × 10(-9) to 1.20 × 10(-6) , resulting in contradicting phylogenies across loci. Nevertheless, beast analyses revealed the species identity and the effects of extrinsic cohesive forces that counteracted the non-stop introgression. As expected, early in speciation with gene flow, only 3-13 loci were highly diverged; two to five outliers (approximately 2.78-6.94% of the genome) were characterized by strong linkage disequilibrium, and asymmetrically distributed among ecotypes, indicating footprints of diversifying selection. In conclusion, ecological speciation of incipient species of Miscanthus probably followed the parapatric model, whereas allopatric speciation cannot be completely ruled out, especially between the geographically isolated northern and southern M. sinensis, for which no significant gene flow across oceanic barriers was detected. Divergence between local ecotypes in early-stage speciation began at a few genomic regions under the influence of natural selection and divergence hitchhiking that overcame gene flow.
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The connexin 30.3 of zebrafish homologue of human connexin 26 may play similar role in the inner ear.
Hear. Res.
PUBLISHED: 04-11-2014
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The intercellular gap junction channels formed by connexins (CXs) are important for recycling potassium ions in the inner ear. CXs are encoded by a family of the CX gene, such as GJB2, and the mechanism leading to mutant connexin-associated diseases, including hearing loss, remains to be elucidated. In this study, using bioinformatics, we found that two zebrafish cx genes, cx27.5 and cx30.3, are likely homologous to human and mouse GJB2. During embryogenesis, zebrafish cx27.5 was rarely expressed at 1.5-3 h post-fertilization (hpf), but a relatively high level of cx27.5 expression was detected from 6 to 96 hpf. However, zebrafish cx30.3 transcripts were hardly detected until 9 hpf. The temporal experiment was conducted in whole larvae. Both cx27.5 and cx30.3 transcripts were revealed significantly in the inner ear by reverse transcription polymerase chain reaction (RT-PCR) and whole-mount in situ hybridization (WISH). In the HeLa cell model, we found that zebrafish Cx27.5 was distributed intracellularly in the cytoplasm, whereas Cx30.3 was localized in the plasma membrane of HeLa cells stably expressing Cx proteins. The expression pattern of zebrafish Cx30.3 in HeLa cells was more similar to that of cells expressing human CX26 than Cx27.5. In addition, we found that Cx30.3 was localized in the cell membrane of hair cells within the inner ear by immunohistochemistry (IHC), suggesting that zebrafish cx30.3 might play an essential role in the development of the inner ear, in the same manner as human GJB2. We then performed morpholino knockdown studies in zebrafish embryos to elucidate the physiological functions of Cx30.3. The zebrafish cx30.3 morphants exhibited wild-type-like and heart edema phenotypes with smaller inner ears at 72 hpf. Based on these results, we suggest that the zebrafish Cx30.3 and mammalian CX26 may play alike roles in the inner ear. Thus, zebrafish can potentially serve as a model for studying hearing loss disorders that result from human CX26 mutations.
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Development and characterization of 16 polymorphic microsatellite markers from Taiwan cow-tail fir, Keteleeria davidiana var. formosana (Pinaceae) and cross-species amplification in other Keteleeria taxa.
BMC Res Notes
PUBLISHED: 02-13-2014
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Keteleeria davidiana var. formosana (Pinaceae), Taiwan cow-tail fir, is an endangered species listed on the IUCN Red List of Threatened Species and only two populations remain, both on the Taiwan Island. Sixteen polymorphic microsatellite loci were developed in an endangered and endemic gymnosperm species, Keteleeria davidiana var. formosana, and were tested in an additional 6 taxa, K. davidiana var. calcarea, K. davidiana var. chienpeii, K. evelyniana, K. fortunei, K. fortunei var. cyclolepis, and K. pubescens, to evaluate the genetic variation available for conservation management and to reconstruct the phylogeographic patterns of this ancient lineage.
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Location and conformation of amyloid ?(25-35) peptide and its sequence-shuffled peptides within membranes: implications for aggregation and toxicity in PC12 Cells.
ChemMedChem
PUBLISHED: 01-27-2014
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Extracellular deposits of amyloid ? (A?) aggregates in the brain is the hallmark of Alzheimer's disease. We present the configurations (location and conformation) and the interfacial folding and membrane insertion mechanisms of A? fragments, wild-type A?(25-35), A?(35-25), and a sequence-shuffled peptide [A?(25-35)-shuffled] from A?(25-35) within membranes by replica-exchange molecular dynamics simulations. Although these peptides have the same amino acid composition, simulations show they have distinct locations and conformations within membranes. Moreover, our in vitro experiments show that these peptides have distinct neurotoxicities. We rationalize the distinct neurotoxicities of these peptides in terms of their simulated locations and conformations in membranes. This work provides another view that complements the general hydrophobicity-toxicity views, to better explain the neurotoxicity of A? peptides.
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Multi-step formation of a hemifusion diaphragm for vesicle fusion revealed by all-atom molecular dynamics simulations.
Biochim. Biophys. Acta
PUBLISHED: 01-04-2014
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Membrane fusion is essential for intracellular trafficking and virus infection, but the molecular mechanisms underlying the fusion process remain poorly understood. In this study, we employed all-atom molecular dynamics simulations to investigate the membrane fusion mechanism using vesicle models which were pre-bound by inter-vesicle Ca(2+)-lipid clusters to approximate Ca(2+)-catalyzed fusion. Our results show that the formation of the hemifusion diaphragm for vesicle fusion is a multi-step event. This result contrasts with the assumptions made in most continuum models. The neighboring hemifused states are separated by an energy barrier on the energy landscape. The hemifusion diaphragm is much thinner than the planar lipid bilayers. The thinning of the hemifusion diaphragm during its formation results in the opening of a fusion pore for vesicle fusion. This work provides new insights into the formation of the hemifusion diaphragm and thus increases understanding of the molecular mechanism of membrane fusion. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy.
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Effects of human Parvovirus B19 and Bocavirus VP1 unique region on tight junction of human airway epithelial A549 cells.
PLoS ONE
PUBLISHED: 01-01-2014
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As is widely recognized, human parvovirus B19 (B19) and human bocavirus (HBoV) are important human pathogens. Obviously, both VP1 unique region (VP1u) of B19 and HBoV exhibit the secreted phospholipase A2 (sPLA2)-like enzymatic activity and are recognized to participate in the pathogenesis of lower respiratory tract illnesses. However, exactly how, both VP1u from B19 and HBoV affect tight junction has seldom been addressed. Therefore, this study investigates how B19-VP1u and HBoV-VP1u may affect the tight junction of the airway epithelial A549 cells by examining phospholipase A2 activity and transepithelial electrical resistance (TEER) as well as performing immunoblotting analyses. Experimental results indicate that TEER is more significantly decreased in A549 cells by treatment with TNF-? (10 ng), two dosages of B19-VP1u and BoV-VP1u (400 ng and 4000 ng) or bee venom PLA2 (10 ng) than that of the control. Accordingly, more significantly increased claudin-1 and decreased occludin are detected in A549 cells by treatment with TNF-? or both dosages of HBoV-VP1u than that of the control. Additionally, more significantly decreased Na+/K+ ATPase is observed in A549 cells by treatment with TNF-?, high dosage of B19-VP1u or both dosages of BoV-VP1u than that of the control. Above findings suggest that HBoV-VP1u rather than B19 VP1u likely plays more important roles in the disruption of tight junction in the airway tract. Meanwhile, this discrepancy appears not to be associated with the secreted phospholipase A2 (sPLA2)-like enzymatic activity.
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Characterization of 42 microsatellite markers from poison ivy, Toxicodendron radicans (Anacardiaceae).
Int J Mol Sci
PUBLISHED: 08-21-2013
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Poison ivy, Toxicodendron radicans, and poison oaks, T. diversilobum and T. pubescens, are perennial woody species of the Anacardiaceae and are poisonous, containing strong allergens named urushiols that cause allergic contact dermatitis. Poison ivy is a species distributed from North America to East Asia, while T. diversilobum and T. pubescens are distributed in western and eastern North America, respectively. Phylogreography and population structure of these species remain unclear. Here, we developed microsatellite markers, via constructing a magnetic enriched microsatellite library, from poison ivy. We designed 51 primer pairs, 42 of which successfully yielded products that were subsequently tested for polymorphism in poison oak, and three subspecies of poison ivy. Among the 42 loci, 38 are polymorphic, while 4 are monomorphic. The number of alleles and the expected heterozygosity ranged from 1 to 12 and from 0.10 to 0.87, respectively, in poison ivy, while varied from 2 to 8 and, from 0.26 to 0.83, respectively in poison oak. Genetic analysis revealed distinct differentiation between poison ivy and poison oak, whereas slight genetic differentiation was detected among three subspecies of poison ivy. These highly polymorphic microsatellite fingerprints enable biologists to explore the population genetics, phylogeography, and speciation in Toxicodendron.
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Synthesis of the decalin core of codinaeopsin via an intramolecular Diels-Alder reaction.
Org. Biomol. Chem.
PUBLISHED: 05-08-2013
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We describe the synthesis of the decalin core of codinaeopsin (1), a tryptophan-polyketide hybrid natural product with promising antimalarial activity (IC50 4.7 ?M, against Plasmodium falciparum), via an intramolecular Diels-Alder (IMDA) reaction. A convergent synthesis was developed to prepare the precursors for the IMDA reaction in 10 steps. The exo cycloadducts were derived from thermal, IMDA reactions of the substrates containing a Weinreb amide or ester conjugated dienophile, and the endo adducts were from Lewis acid promoted reactions of the substrates with a formyl group. Both exo and endo products of the IMDA were exclusively isolated and characterized by NMR spectroscopy. One endo cycloadduct was further confirmed with X-ray crystallography. Theoretical calculations reveal the influence of the substituents of the decalin core on the IMDA process.
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Proteomic analyses and identification of arginine methylated proteins differentially recognized by autosera from anti-Sm positive SLE patients.
J. Biomed. Sci.
PUBLISHED: 04-25-2013
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Antibodies against spliceosome Sm proteins (anti-Sm autoantibodies) are specific to the autoimmune disease systemic lupus erythematosus (SLE). Anti-Sm autosera have been reported to specifically recognize Sm D1 and D3 with symmetric di-methylarginines (sDMA). We investigated if anti-Sm sera from local SLE patients can differentially recognize Sm proteins or any other proteins due to their methylation states.
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A molecular dynamics study of the structural and dynamical properties of putative arsenic substituted lipid bilayers.
Int J Mol Sci
PUBLISHED: 03-01-2013
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Cell membranes are composed mainly of phospholipids which are in turn, composed of five major chemical elements: carbon, hydrogen, nitrogen, oxygen, and phosphorus. Recent studies have suggested the possibility of sustaining life if the phosphorus is substituted by arsenic. Although this issue is still controversial, it is of interest to investigate the properties of arsenated-lipid bilayers to evaluate this possibility. In this study, we simulated arsenated-lipid, 1-palmitoyl-2-oleoyl-sn-glycero-3-arsenocholine (POAC), lipid bilayers using all-atom molecular dynamics to understand basic structural and dynamical properties, in particular, the differences from analogous 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine, (POPC) lipid bilayers. Our simulations showed that POAC lipid bilayers have distinct structural and dynamical properties from those of native POPC lipid bilayers. Relative to POPC lipid bilayers, POAC lipid bilayers have a more compact structure with smaller lateral areas and greater order. The compact structure of POAC lipid bilayers is due to the fact that more inter-lipid salt bridges are formed with arsenate-choline compared to the phosphate-choline of POPC lipid bilayers. These inter-lipid salt bridges bind POAC lipids together and also slow down the head group rotation and lateral diffusion of POAC lipids. Thus, it would be anticipated that POAC and POPC lipid bilayers would have different biological implications.
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Human parvovirus B19 NS1 protein aggravates liver injury in NZB/W F1 mice.
PLoS ONE
PUBLISHED: 02-21-2013
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Human parvovirus B19 (B19) has been associated with a variety of diseases. However, the influence of B19 viral proteins on hepatic injury in SLE is still obscure. To elucidate the effects of B19 viral proteins on livers in SLE, recombinant B19 NS1, VP1u or VP2 proteins were injected subcutaneously into NZB/W F1 mice, respectively. Significant expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were detected in NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Markedly hepatocyte disarray and lymphocyte infiltration were observed in livers from NZB/WF 1 mice receiving B19 NS1 as compared to those mice receiving PBS. Additionally, significant increases of Tumor Necrosis Factor -? (TNF-?), TNF-? receptor, I?B kinase -? (IKK-?), nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor (I?B) and nuclear factor-kappa B (NF-?B) were detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Accordingly, significant increases of matrix metalloproteinase-9 (MMP9) and U-plasminogen activator (uPA) were also detected in livers from NZB/W F1 mice receiving B19 NS1 as compared to those mice receiving PBS. Contrarily, no significant variation on livers from NZB/W F1 mice receiving B19 VP1u or VP2 was observed as compared to those mice receiving PBS. These findings firstly demonstrated the aggravated effects of B19 NS1 but not VP1u or VP2 protein on hepatic injury and provide a clue in understanding the role of B19 NS1 on hepatic injury in SLE.
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Myopericarditis and exertional rhabdomyolysis following an influenza A (H3N2) infection.
BMC Infect. Dis.
PUBLISHED: 02-13-2013
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Acute myopericarditis and exertional rhabdomyolysis, two uncommon but well-described diseases with potentially life-threatening effects, are generally considered as independent clinical entities. However, they may in fact be pathophysiologically related under certain circumstances. This is the first ever report of influenza myopericarditis provoked by exertional rhabdomyolysis to the best of our knowledge.
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Effects of Cystamine on antioxidant activities and regulatory T cells in lupus-prone mice.
J. Cell. Mol. Med.
PUBLISHED: 02-05-2013
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Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus (SLE). Despite the well-established beneficial effects of cystamine on lupus-prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti-oxidant activities in NZB/W F1 mice by performing assays of Glutathione (GSH), 1,1-diphenyl-2- picryl-hydrazyl (DPPH) and malondialdehyde thiobarbituric acid (MDA). In addition, investigations of the effects of cystamine on CD4(+) /CD25(+) regulatory T cells and interleukin-6 (IL6)/STAT-3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB/W F1 mice receiving cystamine than in those mice receiving PBS. Meanwhile, CD4(+) /CD25(+) regulatory T cells more significantly increase in NZB/W F1 mice receiving cystamine than in those mice receiving PBS, accompanied by significantly reduced IL-6/phosphorylated STAT-3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD4(+) /CD25(+) regulatory T cells in lupus-prone mice by suppressing IL-6/STAT3 signalling.
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Molecular mechanism of Ca(2+)-catalyzed fusion of phospholipid micelles.
Biochim. Biophys. Acta
PUBLISHED: 01-24-2013
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Although membrane fusion plays key roles in intracellular trafficking, neurotransmitter release, and viral infection, its underlying molecular mechanism and its energy landscape are not well understood. In this study, we employed all-atom molecular dynamics simulations to investigate the fusion mechanism, catalyzed by Ca(2+) ions, of two highly hydrated 1-palmitoyl-2-oleoyl-sn-3-phosphoethanolamine (POPE) micelles. This simulation system mimics the small contact zone between two large vesicles at which the fusion is initiated. Our simulations revealed that Ca(2+) ions are capable of catalyzing the fusion of POPE micelles; in contrast, we did not observe close contact of the two micelles in the presence of only Na(+) or Mg(2+) ions. Determining the free energy landscape of fusion allowed us to characterize the underlying molecular mechanism. The Ca(2+) ions play a key role in catalyzing the micelle fusion in three aspects: creating a more-hydrophobic surface on the micelles, binding two micelles together, and enhancing the formation of the pre-stalk state. In contrast, Na(+) or Mg(2+) ions have relatively limited effects. Effective fusion proceeds through sequential formation of pre-stalk, stalk, hemifused-like, and fused states. The pre-stalk state is the state featuring lipid tails exposed to the inter-micellar space; its formation is the rate-limiting step. The stalk state is the state where a localized hydrophobic core is formed connecting two micelles; its formation occurs in conjunction with water expulsion from the inter-micellar space. This study provides insight into the molecular mechanism of fusion from the points of view of energetics, structure, and dynamics.
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Cystamine ameliorates ventricular hypertrophy associated with modulation of IL-6-mediated signaling in lupus-prone mice.
Life Sci.
PUBLISHED: 01-09-2013
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The aim of this study is to investigate the protective effects of cystamine on lupus-associated cardiac hypertrophy.
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Exacerbating effects of human parvovirus B19 NS1 on liver fibrosis in NZB/W F1 mice.
PLoS ONE
PUBLISHED: 01-01-2013
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Systemic lupus erythematosus (SLE) is an autoimmune disorder with unknown etiology that impacts various organs including liver. Recently, human parvovirus B19 (B19) is recognized to exacerbate SLE. However, the effects of B19 on liver in SLE are still unclear. Herein we aimed to investigate the effects of B19 on liver in NZB/W F1 mice by injecting subcutaneously with PBS, recombinant B19 NS1, VP1u or VP2, respectively. Our experimental results revealed that B19 NS1 protein significantly enhanced the TGF-?/Smad fibrotic signaling by increasing the expressions of TGF-?, Smad2/3, phosphorylated Smad2/3, Smad4 and Sp1. The consequent fibrosis-related proteins, PAI-1 and ?-SMA, were also significantly induced in livers of NZB/W F1 mice receiving B19 NS1 protein. Accordingly, markedly increased collagen deposition was also observed in livers of NZB/W F1 mice receiving B19 NS1 protein. However, no significant difference was observed in livers of NZB/W F1 mice receiving B19 VP1u or VP2 as compared to the controls. These findings indicate that B19 NS1 plays a crucial role in exacerbating liver fibrosis in NZB/W F1 mice through enhancing the TGF-â/Smad fibrotic signaling.
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Characterization of 24 transferable microsatellite loci in four skullcaps (Scutellaria, Labiatae).
Am. J. Bot.
PUBLISHED: 12-27-2011
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Transferable polymorphic microsatellite loci for four skullcaps, Scutellaria indica, S. taiwanensis, S. austrotaiwanensis, and S. playfairii, were developed for future studies of the mating system and population structure of these species. Interspecific amplification was also tested in various Scutellaria species.
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Effects of human parvovirus B19 on expression of defensins and Toll-like receptors.
Chin J Physiol
PUBLISHED: 12-06-2011
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Both cell-mediated and humoral immunity have been widely investigated for the roles in pathogenesis of human parvovirus B19 (B19) infection. However, little is known about the effects of B19 infection on innate immunity. In the current study, expression of alpha-human neutrophil peptides (HNP) 1-3, alpha-human defensin (HD) 5, HD6, beta-human defensin (hBD)-1, hBD-3, toll-like receptor (TLR) 4, TLR5, TLR7 and TLR9 in B19-nonstructural protein (NS)-1 or B19-viral protein (VP)-2 transfected COS-7 cells was investigated by reverse transcription (RT)-PCR or by western blots. Significantly increased HNP1-3, HD5, HD6, hBD1 and hBD3 mRNA levels were detected at both 24 h and 20 days post-transfection in COS-7 cells transfected with pEGFP-NS1. In pEGFP-VP2-transfected COS-7 cells, significantly increased HNP1-3, HD5, HD6, hBD-1 and hBD-3 mRNA expression levels were observed on day 20, albeit only hBD3 mRNA increased significantly at 24 h post-transfection. Additionally, TLR4, TLR5 and TLR7 proteins decreased significantly in COS-7 cells transfected with pEGFP-NS1 or pEGFP-VP2 at 48 h but significantly increased on day 20. Notably, only TLR9 protein increased significantly in the cells transfected with pEGFP-NS1 on day 20. No significant variation of TLRs was observed in cells transfected with pEGFP-NS1K334E, a single substitution mutantation of B19-NS1 protein without original cytotoxicity, at both 48 h and on day 20. These novel findings revealed the different effects of B19-NS1 and VP2 on the stimulation of defensins and TLRs and could provide a clue in understanding the roles of B19-NS1 and VP2 on innate immunity.
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Development of 12 genic microsatellite loci for a biofuel grass, Miscanthus sinensis (Poaceae).
Am. J. Bot.
PUBLISHED: 07-27-2011
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Miscanthus, a nonfood plant with high potential as a biofuel, has been used in Europe and the United States. The selection of a cultivar with high biomass, photosynthetic efficiency, and stress resistance from wild populations has become an important issue. New genic microsatellite markers will aid the assessment of genetic diversity for different strains.
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Genetic population structure of the alpine species Rhododendron pseudochrysanthum sensu lato (Ericaceae) inferred from chloroplast and nuclear DNA.
BMC Evol. Biol.
PUBLISHED: 04-19-2011
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A complex of incipient species with different degrees of morphological or ecological differentiation provides an ideal model for studying species divergence. We examined the phylogeography and the evolutionary history of the Rhododendron pseudochrysanthum s. l.
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Ameliorate Effects of Li-Fu Formula on IL-6-Mediated Cardiac Hypertrophy in Hamsters Fed with a Hyper-Cholesterol Diet.
Evid Based Complement Alternat Med
PUBLISHED: 03-10-2011
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Hypercholesterolemia diets are considered as major sources to cause cardiac hypertrophy. This study intends to evaluate the effects of Li-Fu formula on cardiac hypertrophy induced by hypercholesterolemia diet. Twenty-four male Golden Syrian hamsters were randomly divided into control, cholesterol and Li-Fu formula groups and fed with different experimental diets for 2 months. Histopathological analysis and western blotting were performed to measure the myocardial architecture, and various cardiac hypertrophy-associated molecules in the excised left ventricle from hamsters. The ratios of whole heart weight/body weight (BW) and left ventricle weight/BW were significantly higher in the cholesterol group but significantly lower in the Li-Fu formula group. The protein levels of both atrial natriuretic peptide and brain natriuretic peptide were significantly increased in the cholesterol group but significantly reduced in the Li-Fu formula group. Additionally, significantly increased interleukin-6, STAT3, MEK5, p-ERK5 and non-cardiomyocyte proliferate signal molecules such as p-MEK and p-ERK, were detected in the cholesterol group but significantly reduced in the Li-Fu formula group. Notably, no significant variations of inflammatory signaling molecules, including p-P38 and p-JNK, were detected in all groups. Our experimental results demonstrated the significant reductions of cardiac hypertrophy and related eccentric hypertrophy signaling, non-cardiomyocyte proliferate signaling in the excised left ventricle of hamsters from the Li-Fu formula. We suggested the protective effects of Li-Fu formula on cardiac hypertrophy that may be useful in prevention or treatment of hypertrophy-associated cardiovascular diseases.
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Potent inhibition of heterotopic ossification by nuclear retinoic acid receptor-? agonists.
Nat. Med.
PUBLISHED: 02-18-2011
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Heterotopic ossification consists of ectopic bone formation within soft tissues after surgery or trauma. It can have debilitating consequences, but there is no definitive cure. Here we show that heterotopic ossification was essentially prevented in mice receiving a nuclear retinoic acid receptor-? (RAR-?) agonist. Side effects were minimal, and there was no significant rebound effect. To uncover the mechanisms of these responses, we treated mouse mesenchymal stem cells with an RAR-? agonist and transplanted them into nude mice. Whereas control cells formed ectopic bone masses, cells that had been pretreated with the RAR-? agonist did not, suggesting that they had lost their skeletogenic potential. The cells became unresponsive to rBMP-2 treatment in vitro and showed decreases in phosphorylation of Smad1, Smad5 and Smad8 and in overall levels of Smad proteins. In addition, an RAR-? agonist blocked heterotopic ossification in transgenic mice expressing activin receptor-like kinase-2 (ALK2) Q207D, a constitutively active form of the receptor that is related to ALK2 R206H found in individuals with fibrodysplasia ossificans progressiva. The data indicate that RAR-? agonists are potent inhibitors of heterotopic ossification in mouse models and, thus, may also be effective against injury-induced and congenital heterotopic ossification in humans.
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Increased cardiac injury in NZB/W F1 mice received antibody against human parvovirus B19 VP1 unique region protein.
Mol. Immunol.
PUBLISHED: 02-11-2011
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Human parvovirus B19 (B19) infection has been postulated to both myocardial injury and development of systemic lupus erythematosus (SLE). However, the influence of anti-B19-VP1u antibodies on cardiac disorders in SLE is still obscure. To elucidate the effects of anti-B19-VP1u IgG in SLE, passive transfer of PBS, normal rabbit IgG or rabbit anti-B19-VP1u IgG was injected intravenously into NZB/W F1 mice, respectively. Significant expression of IL-1?, IL-6 and TNF-? were detected in NZB/W F1 mice receiving rabbit anti-B19-VP1u IgG. Markedly cardiomyocyte disarray and lymphocyte infiltration were observed in left ventricle of hearts from NZB/W F1 mice receiving rabbit anti-B19-VP1u IgG. Additionally, significant increases of matrix metalloproteinase-9 (MMP9) activity and protein expression were detected in left ventricle of hearts from NZB/W F1 mice receiving B19-VP1u IgG. Accordingly, significant increase of phosphorylated p-38 and NF-?B proteins were observed in left ventricle of hearts from NZB/W F1 mice receiving B19-VP1u IgG. However, no significant variation of cardiac atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), heart-type fatty acid-binding protein (h-FABP) and creatine kinase MB (CK-MB) were detected among all experimental groups. These findings firstly demonstrated the aggravated effects of anti-B19 VP1u IgG on cardiac injury by induction of inflammatory but not myocardial infarction-associated proteins through activation of phosphorylated p-38 and NF-?B signaling.
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Synthesis and solid-state NMR characterization of cubic mesoporous silica SBA-1 functionalized with sulfonic acid groups.
J Colloid Interface Sci
PUBLISHED: 01-13-2011
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Well-ordered cubic mesoporous silicas SBA-1 functionalized with sulfonic acid groups have been synthesized through in situ oxidation of mercaptopropyl groups with H(2)O(2) via co-condensation of tetraethoxysilane (TEOS) and 3-mercaptopropyltrimethoxysilane (MPTMS) templated by cetyltriethylammonium bromide (CTEABr) under strong acidic conditions. Various synthesis parameters such as the amounts of H(2)O(2) and MPTMS on the structural ordering of the resultant materials were systematically investigated. The materials thus obtained were characterized by a variety of techniques including powder X-ray diffraction (XRD), multinuclear solid-state Nuclear Magnetic Resonance (NMR) spectroscopy, (29)Si{(1)H} 2D HETCOR (heteronuclear correlation) NMR spectroscopy, thermogravimetric analysis (TGA), and nitrogen sorption measurements. By using (13)C CPMAS NMR technique, the status of the incorporated thiol groups and their transformation to sulfonic acid groups can be monitored and, as an extension, to define the optimum conditions to be used for the oxidation reaction to be quantitative. In particular, (29)Si{(1)H} 2D HETCOR NMR revealed that the protons in sulfonic acid groups are in close proximity to the silanol Q(3) species, but not close enough to form a hydrogen bond.
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Unsymmetrical squaraines incorporating the thiophene unit for panchromatic dye-sensitized solar cells.
Org. Lett.
PUBLISHED: 11-03-2010
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Two unsymmetrical squaraines, where the electron-rich 3,4-ethylenedioxythiophene or bithiophene conjugated fragment was used to link unconventionally the squaraine core and the hexyloxyphenyl amino group, were applied for DSCs. The corresponding photovoltaic devices exhibit an attractively panchromatic response and also convert a portion of the near-infrared photons into electricity.
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A study on low temperature transport properties of independent double-gated poly-Si nanowire transistors.
Nanotechnology
PUBLISHED: 09-29-2010
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Employing mix-and-match lithography of I-line stepper and e-beam direct writing, independent double-gated poly-Si nanowire thin film transistors with channel lengths ranging from 70 nm to 5 µm were fabricated and characterized. Electrical measurements performed under cryogenic ambient displayed intriguing characteristics in terms of length dependent abrupt switching behavior for one of the single-gated modes. Through simulation and experimental verification, the root cause for this phenomenon was identified to be the non-uniformly distributed dopants introduced by ion implantation.
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Designs of broadband and wide-view patterned polarizers for stereoscopic 3D displays.
Opt Express
PUBLISHED: 09-18-2010
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This work presents a new methodology to design patterned circular polarizers consisting of in-cell polarizers, in-cell retarders and biaxial films to achieve very wide viewing freedom for stereoscopic 3D color LCDs. The biaxial films with least materials and simple fabrication concepts are employed for off-axis compensation of the in-cell retarders. In the best result, the crosstalk ratio is less than 0.035 or 0.0082 respectively for over ± 60° or ± 40° viewing cone of the 3D display. As to the normal view of the proposed structure with glasses or LCD rotation, the crosstalk ratio is less than 0.11%, with 93.5% improvement as compared with the ± ?/4 patterned polarizer. The dispersion properties of materials have been considered in all simulations to mimic real situations.
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Multilocus analysis of genetic divergence between outcrossing Arabidopsis species: evidence of genome-wide admixture.
New Phytol.
PUBLISHED: 07-28-2010
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• Outcrossing Arabidopsis species that diverged from their inbreeding relative Arabidopsis thaliana 5 million yr ago and display a biogeographical pattern of interspecific sympatry vs intraspecific allopatry provides an ideal model for studying impacts of gene introgression and polyploidization on species diversification. • Flow cytometry analyses detected ploidy polymorphisms of 2× and 4× in Arabidopsis lyrata ssp. kamchatica of Taiwan. Genomic divergence between species/subspecies was estimated based on 98 randomly chosen nuclear genes. Multilocus analyses revealed a mosaic genome in diploid A. l. kamchatica composed of Arabidopsis halleri-like and A. lyrata-like alleles. • Coalescent analyses suggest that the segregation of ancestral polymorphisms alone cannot explain the high inconsistency between gene trees across loci, and that gene introgression via diploid A. l. kamchatica likely distorts the molecular phylogenies of Arabidopsis species. However, not all genes migrated across species freely. Gene ontology analyses suggested that some nonmigrating genes were constrained by natural selection. • High levels of estimated ancestral polymorphisms between A. halleri and A. lyrata suggest that gene flow between these species has not completely ceased since their initial isolation. Polymorphism data of extant populations also imply recent gene flow between the species. Our study reveals that interspecific gene flow affects the genome evolution in Arabidopsis.
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Proteomic analysis for the anti-apoptotic effects of cystamine on apoptosis-prone macrophage.
J. Cell. Biochem.
PUBLISHED: 06-01-2010
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Increased macrophage vulnerability is associated with progression of systemic lupus erythematosus. Our previous studies have shown that cystamine, an inhibitor of transglutaminase 2 (TG2), alleviated the apoptosis of hepatocyte and brain cell in lupus-prone mice NZB/W-F1. In present study, we further investigated the effects of cystamine on apoptosis-prone macrophages (APMs) in the lupus mice. Using two-dimensional gel electrophoresis (2-DE) analysis, we found that cystamine induced a differential protein expression pattern of APM as comparing to the PBS control. The protein spots presenting differential level between cystamine and PBS treatment were then identified by peptide-mass fingerprinting (PMF). After bioinformatic analysis, these identified proteins were found involved in mitochondrial apoptotic pathway, oxidative stress, and mitogen-activated protein (MAP) kinase-mediated pathway. Further investigation revealed that cystamine significantly decreased the levels of apoptotic Bax and Apaf-1 and the activity of caspase-3, and increased the levels of anti-apoptotic Bcl-2 in APM. We also found that these apoptotic mediators were up-regulated in a correlation with the progression of lupus severity in NZB/W-F1, which were little affected in BALB/c mice. We also found that the reduced serum glutathione was restored by cystamine in NZB/W-F1. Interestingly, the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) in APM and the phagocytic ability was diminished in presence of cystamine. In conclusion, our findings indicate that cystamine significantly inhibited mitochondrial pathway, induced antioxidant proteins, and diminished phosphorylation of extracellular ERK1/2, which may alleviate the apoptosis and the phagocytic ability of APM.
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Human parvovirus B19 nonstructural protein NS1 enhanced the expression of cleavage of 70 kDa U1-snRNP autoantigen.
J. Biomed. Sci.
PUBLISHED: 05-25-2010
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Human parvovirus B19 (B19) is known to induce apoptosis that has been associated with a variety of autoimmune disorders. Although we have previously reported that B19 non-structural protein (NS1) induces mitochondrial-dependent apoptosis in COS-7 cells, the precise mechanism of B19-NS1 in developing autoimmunity is still obscure.
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Expression of anti-cardiolipin antibodies and inflammatory associated factors in patients with schizophrenia.
Psychiatry Res
PUBLISHED: 04-02-2010
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Numerous studies have implicated a connection between schizophrenia and autoimmune disorders. However, the precise relationship and underlying mechanism are still obscure. To further identify the association between autoimmune disorders and schizophrenia, the mRNA expressions of various cytokines and Toll-like receptors (TLRs) in monocytes are examined by using RT-PCR. Additionally, ELISA and zymography were performed to determine the anti-cardiolipin antibody (aCL) and MMP9 activity in serum form schizophrenic patients. Notably, significantly increased interleukin (IL)-6 and IL-10 mRNA were observed in schizophrenic patients, whereas significant reductions of TLR-3 and TLR-5 mRNA were detected. Moreover, significantly increased levels of aCL antibody and a higher frequency of positive-MMP9 activity were detected in serum from patients with schizophrenia. Meanwhile, no significant association was found between each of the medications and aCL activity. These findings demonstrated autoimmune-related phenomena in schizophrenic patients and further suggested a connection between schizophrenia and autoimmune disorders.
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Folding and membrane insertion of amyloid-beta (25-35) peptide and its mutants: implications for aggregation and neurotoxicity.
Proteins
PUBLISHED: 03-16-2010
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The mechanisms of interfacial folding and membrane insertion of the Alzheimers amyloid-beta fragment Abeta(25-35) and its less toxic mutant, N27A-Abeta(25-35) and more toxic mutant, M35A-Abeta(25-35), are investigated using replica-exchange molecular dynamics in an implicit water-membrane environment. This study simulates the processes of interfacial folding and membrane insertion in a spontaneous fashion to identify their general mechanisms. Abeta(25-35) and N27A-Abeta(25-35) peptides share similar mechanisms: the peptides are first located in the membrane hydrophilic region where their C-terminal residues form helical structures. The peptides attempt to insert themselves into the membrane hydrophobic region using the C-terminal or central hydrophobic residues. A small portion of peptides can successfully enter the membranes hydrophobic core, led by their C-terminal residues, through the formation of continuous helical structures. No detectable amount of M35A-Abeta(25-35) peptides appeared to enter the membranes hydrophobic core. The three studied peptides share a similar helical structure for their C-terminal five residues, and these residues mainly buried within the membranes hydrophobic region. In contrast, their N-terminal properties are markedly different. With respect to the Abeta(25-35), the N27A-Abeta(25-35) forms a more structured helix and is buried deeper within the membrane, which may result in a lower degree of aggregation and a lower neurotoxicity; in contrast, the less structured and more water-exposed M35A-Abeta(25-35) is prone to aggregation and has a higher neurotoxicity. Understanding the mechanisms of Abeta peptide interfacial folding and membrane insertion will provide new insights into the mechanisms of neurodegradation and may give structure-based clues for rational drug design preventing amyloid associated diseases.
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Identification of an autoantibody against the proliferating cell nuclear antigen from a patient with systemic lupus erythematosus.
Chin J Physiol
PUBLISHED: 02-28-2010
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Antibodies against the proliferating cell nuclear antigen (PCNA) was first discovered in the sera of systemic lupus erythematosus (SLE) patients. However, the reactivity and specificity of anti-PCNA autoantibodies are still unclear. To investigate the property of anti-PCNA autoantibodies, we conducted an ELISA screening of the anti-PCNA autoantibodies in sera of SLE patients. Eighteen out of 191 SLE sera were found to be positive for anti-PCNA antibodies giving a frequency of nearly 10%. Among the positive sera, a sample with the highest titer of anti-PCNA autoantibody preferentially recognizes the wild-type PCNA as compared to the Y114A mutation which contains a single amino acid substitution at 114 and fails to form the toroidal structure. Moreover, the autoantibody purified from this serum identifies only the free PCNA in crude mammalian cell extracts but not other associated cellular components. This finding raises a possibility that immunostaining with the human anti-PCNA autoantibodies in previous studies might have only partially PCNAs in tissues.
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TD-DFT study of the excited-state potential energy surfaces of 2-(2-hydroxyphenyl)benzimidazole and its amino derivatives.
J Phys Chem A
PUBLISHED: 02-27-2010
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In this study, we used TD-PBE0 calculations to investigate the first singlet excited state (S(1)) behavior of 2-(2-hydroxyphenyl)benzimidazole (HBI) and its amino derivatives. We employed the potential energy surfaces (PESs) at the S(1) state covering the normal syn, tautomeric (S(1)-T(syn)), and intramolecular charge-transfer (S(1)-T(ICT)) states in ethanol and cyclohexane to investigate the reaction mechanisms, including excited-state intramolecular proton transfer (ESIPT) and intramolecular charge-transfer (ICT) processes. Two new S(1)-T(ICT) states, stable in ethanol and cyclohexane, were found for HBI and its amino derivatives; they are twisted and pyramidalized. The flat PES of the ICT process makes the S(1)-T(ICT) states accessible. The S(1)-T(ICT) state is effective for radiationless relaxation, which is responsible for quenching the fluorescence of the S(1)-T(syn) state. In contrast to the situation encountered conventionally, the S(1)-T(ICT) state does not possess a critically larger dipole moment than its precursor, S(1)-T(syn) state; hence, it is not particularly stable in polar solvents. On the basis of the detailed PESs, we rationalize various experimental observations complementing previous studies and provide insight to understand the excited-state reaction mechanisms of HBI and its amino derivatives.
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The association of anti-parvovirus B19-VP1 unique region antibodies with antiphospholipid antibodies in patients with antiphospholipid syndrome.
Clin. Chim. Acta
PUBLISHED: 01-31-2010
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Human parvovirus B19 (B19) infection has been identified as a trigger of antiphospholipid syndrome (APS). However, the precise role of B19-VP1 unique region (VP1u) in patients with antiphospholipid syndrome remains unclear.
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Beneficial effects of taurine on cardiac abnormality in NZB/W F1 mice fed with a high-cholesterol diet.
J. Agric. Food Chem.
PUBLISHED: 08-15-2009
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A significantly higher prevalence of cardiovascular disease (CVD) is reported in patients with systemic lupus erythematosus (SLE) as compared with the general population and accounts for approximately 30% of deaths in SLE patients. However, the mechanism of and treatments for CVD in patients with SLE are still unclear. To explore the effects of taurine on cardiac abnormality in SLE, NZB/W F1 mice were used as the experimental model by receiving control, cholesterol, or cholesterol/taurine diets, respectively. Improved cardiac histopathological changes were observed in left ventricle tissues from the cholesterol/taurine group as compared to the control or cholesterol group. Significant reductions of TUNEL-positive cells, Fas death receptor-related components, mitochondrial-dependent apoptosis, cardiac fibrosis, and fibrotic signaling components were detected in the left ventricle tissues from the cholesterol/taurine group as compared to the control or cholesterol group. Additionally, cardiac IGR1R survival signaling components were significantly increased in the left ventricle tissues from the cholesterol/taurine group as compared to the control or cholesterol group. These findings revealed the protective effects of taurine against the cardiac abnormalities in NZB/W F1 mice and may suggest the potential for clinical application of taurine in treatment of CVD in SLE.
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Extracellular matrix controls insulin signaling in mammary epithelial cells through the RhoA/Rok pathway.
J. Cell. Physiol.
PUBLISHED: 04-25-2009
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Cellular responses are determined by a number of signaling cues in the local microenvironment, such as growth factors and extracellular matrix (ECM). In cultures of mammary epithelial cells (MECs), functional differentiation requires at least two types of signal, lactogenic hormones (i.e., prolactin, insulin, and hydrocortisone) and the specialized ECM, basement membrane (BM). Our previous work has shown that ECM affects insulin signaling in mammary cells. Cell adhesion to BM promotes insulin-stimulated tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and association of PI3K with IRS-1, whereas cells cultured on stromal ECM are inefficient in transducing these post-receptor events. Here we examine the mechanisms underlying ECM control of IRS phosphorylation. Compared to cells cultured on BM, cells on plastic exhibit higher level of RhoA activity. The amount and the activity of Rho kinase (Rok) associated with IRS-1 are greater in these cells, leading to serine phosphorylation of IRS-1. Expression of dominant negative RhoA and the application of Rok inhibitor Y27632 in cells cultured on plastic augment tyrosine phosphorylation of IRS-1. Conversely, expression of constitutively active RhoA in cells cultured on BM impedes insulin signaling. These data indicate that RhoA/Rok is involved in substratum-mediated regulation of insulin signaling in MECs, and under the conditions where proper adhesion to BM is missing, such as after wounding and during mammary gland involution, insulin-mediated cellular differentiation and survival would be defective.
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Anti-human parvovirus B19 nonstructural protein antibodies in patients with rheumatoid arthritis.
Clin. Chim. Acta
PUBLISHED: 04-04-2009
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Previous studies have reported the association between the development of NS1-specific IgG and arthropathy after the infection of human parvovirus B19 (B19). However, the role of anti-B19-NS1 IgG in RA is still unclear. This study investigated the role of anti-B19-NS1 antibody in patients with rheumatoid arthritis (RA).
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Coupling molecular dynamics simulations with experiments for the rational design of indolicidin-analogous antimicrobial peptides.
J. Mol. Biol.
PUBLISHED: 03-10-2009
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Antimicrobial peptides (AMPs) have attracted much interest in recent years because of their potential use as new-generation antibiotics. Indolicidin (IL) is a 13-residue cationic AMP that is effective against a broad spectrum of bacteria, fungi, and even viruses. Unfortunately, its high hemolytic activity retards its clinical applications. In this study, we adopted molecular dynamics (MD) simulations as an aid toward the rational design of IL analogues exhibiting high antimicrobial activity but low hemolysis. We employed long-timescale, multi-trajectory all-atom MD simulations to investigate the interactions of the peptide IL with model membranes. The lipid bilayer formed by the zwitterionic 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) was chosen as the model erythrocyte membrane; lipid bilayers formed from a mixture of POPC and the negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol were chosen to model bacterial membranes. MD simulations with a total simulation time of up to 4 micros revealed the mechanisms of the processes of IL adsorption onto and insertion into the membranes. The packing order of these lipid bilayers presumably correlated to the membrane stability upon IL adsorption and insertion. We used the degree of local membrane thinning and the reduction in the order parameter of the acyl chains of the lipids to characterize the membrane stability. The order of the mixed 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol/POPC lipid bilayer reduced significantly upon the adsorption of IL. On the other hand, although the order of the pure-POPC lipid bilayer was perturbed slightly during the adsorption stage, the value was reduced more dramatically upon the insertion of IL into the membranes hydrophobic region. The results imply that enhancing IL adsorption on the microbial membrane may amplify its antimicrobial activity, while the degree of hemolysis may be reduced through inhibition of IL insertion into the hydrophobic region of the erythrocyte membrane. In addition, through simulations, we identified the amino acids that are most responsible for the adsorption onto or insertion into the two model membranes. Positive charges are critical to the peptides adsorption, whereas the presence of hydrophobic Trp8 and Trp9 leads to its deeper insertion. Combining the hypothetical relationships between the membrane disordering and the antimicrobial and hemolytical activities with the simulated results, we designed three new IL-analogous peptides: IL-K7 (Pro7-->Lys), IL-F89 (Trp8 and Trp9-->Phe), and IL-K7F89 (Pro7-->Lys; Trp8 and Trp9-->Phe). The hemolytic activity of IL-F89 is considerably lower than that of IL, whereas the antimicrobial activity of IL-K7 is greatly enhanced. In particular, the de novo peptide IL-K7F89 exhibits higher antimicrobial activity against Escherichia coli; its hemolytic activity decreased to only 10% of that of IL. Our simulated and experimental results correlated well. This approach-coupling MD simulations with experimental design-is a useful strategy toward the rational design of AMPs for potential therapeutic use.
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The effect of local nasal immunotherapy in allergic rhinitis: using strips of the allergen dermatophagoides pteronyssinus.
J Asthma
PUBLISHED: 03-03-2009
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Local nasal immunotherapy (LNIT) has been reported to be effective for mite-induced allergic rhinitis. However, its compliance is poor due to persistent nasal reactions and difficult application. The main objective of this study was to develop a Dermatophagoides pteronyssinus (Der p)-coated strip for self-application and to evaluate its clinical efficacy. Randomized, double-blind, placebo-controlled trials were carried out to evaluate the efficacy and compliance of LNIT. A total of 35 patients with allergic rhinitis from the allergy clinic were recruited to receive four months of LNIT. Clinical efficacy was evaluated by the symptoms of sneezing, rhinorrhea and nasal stuffiness. Local and systemic effects were evaluated by measuring histamine and eosinophil cationic protein (ECP) in nasal discharge and allergen-specific IgG1, IgG4 and IgE in sera. LNIT with Der p-coated strips could reduce nasal symptoms and modulate the serum levels of Der p-specific IgG1, IgG4 and IgE. The secretion of both histamine and ECP was reduced within four months after treatment. When the symptomatic and immunological changes were compared between active treatment and placebo groups, the improvements were greater in the active treatment groups for all three symptom scores. There were no severe adverse events except nasal response persisting within the first month in some cases. LNIT with a steady dose of Der p-coated strips can be self-administered at home without any systemic reactions. Both local and systemic immune responses were observed after LNIT. This therapeutic modality may serve as a good alternative treatment for allergic rhinitis.
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Increased expression of Matrix Metalloproteinase 9 in liver from NZB/W F1 mice received antibody against human parvovirus B19 VP1 unique region protein.
J. Biomed. Sci.
PUBLISHED: 01-26-2009
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Human parvovirus B19 infection has been postulated to the anti-phospholipid syndrome (APS) in autoimmunity. However, the influence of anti-B19-VP1u antibody in autoimmune diseases is still obscure.
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Effects of human parvovirus B19 VP1 unique region protein on macrophage responses.
J. Biomed. Sci.
PUBLISHED: 01-24-2009
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Activity of secreted phospholipase A (sPLA2) has been implicated in a wide range of cellular responses. However, little is known about the function of human parvovirus B19-VP1 unique region (VP1u) with sPLA2 activity on macrophage.
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Paraphyly of organelle DNAs in Cycas Sect. Asiorientales due to ancient ancestral polymorphisms.
BMC Evol. Biol.
PUBLISHED: 01-23-2009
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This study addresses the apportionment of genetic diversity between Cycas revoluta and C. taitungensis, species that constitute the section Asiorientales and represent a unique, basal lineage of the Laurasian genus Cycas. Fossil evidence indicates divergence of the section from the rest of Cycas at least 30 million years ago. Geographically, C. taitungensis is limited to Taiwan whereas C. revoluta is found in the Ryukyu Archipelago and on mainland China.
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Isolation and characterization of polymorphic microsatellite loci from Areca catechu (Arecaceae) using PCR-based isolation of microsatellite arrays.
Mol Ecol Resour
PUBLISHED: 01-16-2009
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Betel nut (Areca nut, Areca catechu L.) is a conspicuous and important cultivated plant of tropical and subtropical habitats throughout Southeast Asia and Oceania. As a significant cultural and social offering, the migration of betel nut associated with human dispersal is an important issue in ethnobotany and anthropology. In this study, we described the development of nine microsatellite loci from A. catechu. The number of alleles per locus ranged from 5 to 15. The expected and observed heterozygosities ranged from 0.71to 0.94 and from 0 to 0.88, respectively. All microsatellite loci, except for AC30, significantly deviated from Hardy-Weinberg equilibrium possibly due to artificially selected cultivation or the existence of excessive null alleles. No linkage disequilibrium was observed from pairwise comparisons of loci, except for AC06 and AC08.
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Cystamine attenuates the expressions of NOS- and TLR-associated molecules in the brain of NZB/W F1 mice.
Eur. J. Pharmacol.
PUBLISHED: 01-07-2009
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Evidence have indicated the impairment of central nervous system (CNS) and neuropsychiatric disorder in patients with systemic lupus erythematosus (SLE). However, little is known to improve the brain abnormality in SLE. To investigate the effect of cystamine on brain abnormality in SLE, NZB/W F1 mice were used as the animal model. Notably, significantly reduced neural Nitric Oxide Synthase (nNOS), inducible Nitric Oxide Synthase (iNOS), p53, p21(WAF1/CIP1), and heat shock protein (HSP)-90 proteins were detected in the brain of NZB/W F1 mice that were treated with cystamine. In contrast, no variation was observed between the brain samples of BALB/c mice that were treated with PBS or cystamine. Moreover, significantly reduced Toll-like receptors- (TLR-) 4, 5 and 7 were detected in the brain samples of NZB/W F1 mice that were treated with cystamine whereas no variation of TLR-4, TLR-5, TLR-7, and TLR-9 was observed in BALB/c mice that were treated with PBS or cystamine. These findings demonstrated the beneficial effects of cystamine on brain abnormality in NZB/W F1 mice and probably suggested the potential of cystamine on treating patients with neuropsychiatric SLE.
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Characterization of 21 microsatellite markers from cogongrass, Imperata cylindrica (Poaceae), a weed species distributed worldwide.
Am. J. Bot.
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Microsatellite loci were developed from Imperata cylindrica, a traditional medicinal herb in Asia and among the top 10 worst invasive weeds in the world, to aid in the identification of the limits of asexual clonal individuals.
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Inferring multiple refugia and phylogeographical patterns in Pinus massoniana based on nucleotide sequence variation and DNA fingerprinting.
PLoS ONE
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Pinus massoniana, an ecologically and economically important conifer, is widespread across central and southern mainland China and Taiwan. In this study, we tested the central-marginal paradigm that predicts that the marginal populations tend to be less polymorphic than the central ones in their genetic composition, and examined a founders effect in the island population.
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A three-dimensional stereoscopic monitor system in microscopic vascular anastomosis.
Microsurgery
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Microvascular procedures not only demand precise movements but also usually require a long operation time. Using a conventional surgical microscope, microvascular surgeons need to keep the neck in a fixed flexion posture, which can lead to physical fatigue. Thus, our aim was to develop a three-dimensional (3D) monitoring system to improve the microsurgery environment. It consists of four main parts: the surgical microscope, the charge-coupled devices, the 3D multiplexer, and the 3D monitor. Two patients with head and neck cancers who underwent tumor resections were reconstructed with free flap microsurgeries. Both artery anastomoses were completed successfully and the postoperative courses of the two patients were smooth. Vascular anastomosis can be performed successfully with the help of the new 3D display system. Although the artery anastomosis procedures took longer than under a surgical microscope, the 3D system offers another option to improve the working environment for surgeons.
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Beneficial Effects of Ocimum gratissimum Aqueous Extract on Rats with CCl(4)-Induced Acute Liver Injury.
Evid Based Complement Alternat Med
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Ocimum gratissimum (OG) is known as a food spice and traditional herb, which has been recommended for the treatment of various diseases. To investigate the hepatoprotective effect of OG aqueous extract (OGAE), male Wistar rats challenged by carbon tetrachloride (CCl(4)) were used as the animal model of chronic hepatic injury. Significantly increased serum catalase and DPPH levels were detected in CCl(4)-administrated rats that were treated with OGAE or silymarin as compared to those rats that were treated with saline or CCl(4). In contrast, significantly decreased stress proteins including HSP70 and iNOS were observed in livers of CCl(4)-administrated rats that were treated with OGAE or sylimarin as compared to those rats that were treated with saline or CCl(4). Moreover, significant decreases of MMP-9/MMP-2 ratio, uPA, phosphorylated ERK (p-ERK) and NF-?B (p-P65) were detected in livers of CCl(4)-administrated rats that were treated with OGAE or sylimarin as compared to those rats that were treated with saline or CCl(4). These findings imply that OGAE can efficiently inhibit CCl(4)-induced liver injuries in rats and may therefore be a potential food or herb for preventing liver injuries.
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Molecular dynamics simulation of cation-phospholipid clustering in phospholipid bilayers: possible role in stalk formation during membrane fusion.
Biochim. Biophys. Acta
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In this study, we performed all-atom long-timescale molecular dynamics simulations of phospholipid bilayers incorporating three different proportions of negatively charged lipids in the presence of K(+), Mg(2+), and Ca(2+) ions to systemically determine how membrane properties are affected by cations and lipid compositions. Our simulations revealed that the binding affinity of Ca(2+) ions with lipids is significantly stronger than that of K(+) and Mg(2+) ions, regardless of the composition of the lipid bilayer. The binding of Ca(2+) ions to the lipids resulted in bilayers having smaller lateral areas, greater thicknesses, greater order, and slower rotation of their lipid head groups, relative to those of corresponding K(+)- and Mg(2+)-containing systems. The Ca(2+) ions bind preferentially to the phosphate groups of the lipids. The complexes formed between the cations and the lipids further assembled to form various multiple-cation-centered clusters in the presence of anionic lipids and at higher ionic strength-most notably for Ca(2+). The formation of cation-lipid complexes and clusters dehydrated and neutralized the anionic lipids, creating a more-hydrophobic environment suitable for membrane aggregation. We propose that the formation of Ca(2+)-phospholipid clusters across apposed lipid bilayers can work as a "cation glue" to adhere apposed membranes together, providing an adequate configuration for stalk formation during membrane fusion.
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Isolation and characterization of 15 microsatellite loci in four endangered Amentotaxus species (Taxaceae).
Am. J. Bot.
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Fifteen microsatellite loci were developed in an endangered species, Amentotaxus formosana, and were tested in an additional three species, A. argotaenia, A. yunnanensis, and A. poilanei, to evaluate the population structure for conservation efforts and reconstruct the phylogeographic patterns of this ancient lineage.
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Evolutionary rates of commonly used nuclear and organelle markers of Arabidopsis relatives (Brassicaceae).
Gene
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Recovering the genetic divergence between species is one of the major interests in the evolutionary biology. It requires accurate estimation of the neutral substitution rates. Arabidopsis thaliana, the first whole-genome sequenced plant, and its out-crossing relatives provide an ideal model for examining the split between sister species. In the study, rates of molecular evolution at markers frequently used for systematics and population genetics, including 14 nuclear genes spanning most chromosomes, three noncoding regions of chloroplast genome, and one intron of mitochondrial genome, between A. thaliana and four relatives were estimated. No deviation from neutrality was detected in the genes examined. Based on the known divergence between A. thaliana and its sisters about 8.0-17.6 MYA, evolutionary rates of the eighteen genes were estimated. Accordingly, the ratio of rates of synonymous substitutions among mitochondrial, chloroplast and nuclear genes was calculated with an average and 95% confidence interval of 1 (0.25-1.75): 15.77 (7.48-114.09): 74.79 (36.27-534.61). Molecular evolutionary rates of nuclear genes varied, with a range of 0.383-0.856×10(-8) for synonymous substitutions per site per year and 0.036-0.081×10(-9) for nonsynonymous substitutions per site per year. Compared with orthologs in Populus, a long life-span tree, genes in Arabidopsis evolved faster in an order of magnitude at the gene level, agreeing with a generation time hypothesis. The estimated substitution rates of these genes can be used as a reference for molecular dating.
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Significant association of past parvovirus B19 infection with cytopenia in both adult-onset Stills disease and systemic lupus erythematosus patients.
Clin. Chim. Acta
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Human parvovirus B19 (B19) infection has been reported as a possible cause of autoimmune diseases. The association of B19 infection with adult-onset Stills diseases (AOSD) remains unclear.
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Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2011-30 November 2011.
Mol Ecol Resour
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This article documents the addition of 139 microsatellite marker loci and 90 pairs of single-nucleotide polymorphism sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Aglaoctenus lagotis, Costus pulverulentus, Costus scaber, Culex pipiens, Dascyllus marginatus, Lupinus nanus Benth, Phloeomyzus passerini, Podarcis muralis, Rhododendron rubropilosum Hayata var. taiwanalpinum and Zoarces viviparus. These loci were cross-tested on the following species: Culex quinquefasciatus, Rhododendron pseudochrysanthum Hay. ssp. morii (Hay.) Yamazaki and R. pseudochrysanthum Hayata. This article also documents the addition of 48 sequencing primer pairs and 90 allele-specific primers for Engraulis encrasicolus.
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Footprints of natural and artificial selection for photoperiod pathway genes in Oryza.
Plant J.
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Asian rice, Oryza sativa, consists of two major subspecies, indica and japonica, which are physiologically differentiated and adapted to different latitudes. Genes for photoperiod sensitivity are likely targets of selection along latitude. We examined the footprints of natural and artificial selections for four major genes of the photoperiod pathway, namely PHYTOCHROME B (PhyB), HEADING DATE 1 (Hd1), HEADING DATE 3a (Hd3a), and EARLY HEADING DATE 1 (Ehd1), by investigation of the patterns of nucleotide polymorphisms in cultivated and wild rice. Geographical subdivision between tropical and subtropical O. rufipogon was found for all of the photoperiod genes in plants divided by the Tropic of Cancer (TOC). All of these genes, except for PhyB, were characterized by the existence of clades that split a long time ago and that corresponded to latitudinal subdivisions, and revealed a likely diversifying selection. Ssp. indica showed close affinity to tropical O. rufipogon for all genes, while ssp. japonica, which has a much wider range of distribution, displayed complex patterns of differentiation from O. rufipogon, which reflected various agricultural needs in relation to crop yield. In japonica, all genes, except Hd3a, were genetically differentiated at the TOC, while geographical subdivision occurred at 31°N in Hd3a, probably the result of varying photoperiods. Many other features of the photoperiod genes revealed domestication signatures, which included high linkage disequilibrium (LD) within genes, the occurrence of frequent and recurrent non-functional Hd1 mutants in cultivated rice, crossovers between subtropical and tropical alleles of Hd1, and significant LD between Hd1 and Hd3a in japonica and indica.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.