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Find video protocols related to scientific articles indexed in Pubmed.
Screening for voltage-gated sodium channel interacting peptides.
Sci Rep
PUBLISHED: 03-18-2014
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The voltage-gated sodium channel (VGSC) interacting peptide is of special interest for both basic research and pharmaceutical purposes. In this study, we established a yeast-two-hybrid based strategy to detect the interaction(s) between neurotoxic peptide and the extracellular region of VGSC. Using a previously reported neurotoxin JZTX-III as a model molecule, we demonstrated that the interactions between JZTX-III and the extracellular regions of its target hNav1.5 are detectable and the detected interactions are directly related to its activity. We further applied this strategy to the screening of VGSC interacting peptides. Using the extracellular region of hNav1.5 as the bait, we identified a novel sodium channel inhibitor SSCM-1 from a random peptide library. This peptide selectively inhibits hNav1.5 currents in the whole-cell patch clamp assays. This strategy might be used for the large scale screening for target-specific interacting peptides of VGSCs or other ion channels.
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Cloning, expression of Aspergillus niger JL-15 endo-polygalacturonase A gene in Pichia pastoris and oligo-galacturonates production.
Protein Expr. Purif.
PUBLISHED: 06-27-2013
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The endo-galacturonase A gene (pgaA) was cloned using the cDNAs synthesized from total RNA of Aspergillus niger JL-15 by reverse transcription as template. The open reading frame (ORF) of pgaA was 1113bp, encoding a peptide of 370 amino acids with the predicted molecular mass of 38.8kDa. The pgaA was successfully expressed in Pichia pastoris GS115 under the control of AOX1 promoter. After induction by methanol for 96h, the activity of the recombinant endo-galacturonase A (rePgaA) in culture supernatant was 2091.0U/mg. SDS-PAGE analysis showed that the molecular mass of rePgaA was about 40.0kDa. Enzymatic properties assays showed that the optimum temperature and pH for rePgaA were 50°C and pH 5.0, respectively. The Michaelis-Menten constant (Km) and maximal velocity (Vmax) of rePgaA for citrus pectin were 3.20mgml(-1) and 40.97?molmin(-1)ml(-1), respectively. The rePgaA mediated a rapid decrease in viscosity of pectin solution with release of small amount of reducing sugar. High performance liquid chromatography (HPLC) analysis revealed that digalacturonate (G2) and trigalalcturonate (G3) were the main hydrolysis products released from pectin by rePgaA. The rePgaA showed very low activity on G2 and G3, which suggested it was a typical endo-acting enzyme.
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The helical surface states of the S-covered topological insulator Sb2Te3(0001).
J Phys Condens Matter
PUBLISHED: 06-13-2013
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The effects of S atom surface adsorption and substitution on the helical surface states of Sb2Te3 are studied by the density-functional theory with spin-orbit coupling being taken into account self-consistently. It is found that S atoms play the role of surface passivation when adsorbed on both surfaces of a 6QL Sb2Te3 film in symmetrical configuration. For symmetrical surfaces with both the top and bottom surfaces of a thin film with adsorbed S atoms, the linear dispersion of the surface states is found to be preserved and the topological surface states survive. The spatial distribution of charge density of the surface state at the ?[overline] point is also symmetric. For a film with asymmetric S atom adsorption, i.e., only one of the surfaces has adsorbed S atoms, the surface band structure is found to be very different. The degeneracy of the surface states from the two sides of a film is broken. The gap opens slightly at ?[overline] and the spatial distribution of charge density of the surface state at the ?[overline] point is also modified greatly. The Fermi level is robust against S impurity adsorption on the surface of Sb2Te3. Compared with S substitution, the effect of single surface S adsorption on electron structures is more prominent. This supports the idea that the topological insulator surface electronic states are dominated by its structural symmetry and the effect of the asymmetric environment of topological insulator Sb2Te3 films should thus be considered.
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Simultaneous detection and degradation patterns of kresoxim-methyl and trifloxystrobin residues in citrus fruits by HPLC combined with QuEChERS.
J Environ Sci Health B
PUBLISHED: 03-05-2013
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This study aimed to investigate the residues, kinetics and dissipation patterns of kresoxim-methyl, (E)-methoxyimino[?-(o-tolyloxy)-o-tolyl]acetate, and trifloxystrobin, methyl(E)-methoxyimino-{(E)-?[1-(?,?,?-trifluoro-m-tolyl)ethylideneaminooxy]-o-tolyl}acetate". A simple and sensitive liquid chromatography-ultraviolet detection (LC-UV) method combined with the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) protocol was developed to quantify the levels of kresoxim-methyl and trifloxystrobin residues in citrus. More than 97% of the kresoxim-methyl and trifloxystrobin deposists gradually dissipated from the citrus peels within 15 days. The half-lives of kresoxim-methyl and trifloxystrobin in the peels were in the ranges of 2.63-2.66 d and 3.12-3.15 d, respectively, and the pattern of decline in the peels followed first-order kinetics. The kresoxim-methyl and trifloxystrobin residues in the pulp dissipated below the detectable level of 0.01 mg kg(-1) after 9 days. Kresoxim-methyl and trifloxystrobin were easily decomposed (T1/2 < 30 d), and the observed dissipation patterns could support the application of these two fungicides in the postharvest storage of citrus fruits.
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Tail tip proteins related to bacteriophage ? gpL coordinate an iron-sulfur cluster.
J. Mol. Biol.
PUBLISHED: 01-11-2013
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The assembly of long non-contractile phage tails begins with the formation of the tail tip complex (TTC). TTCs are multi-functional protein structures that mediate host cell adsorption and genome injection. The TTC of phage ? is assembled from multiple copies of eight different proteins, including gpL. Purified preparations of gpL and several homologues all displayed a distinct reddish color, suggesting the binding of iron by these proteins. Further characterization of the gpL homologue from phage N15, which was most amenable to in vitro analyses, showed that it contains two domains. The C-terminal domain was demonstrated to coordinate an iron-sulfur cluster, providing the first example of a viral structural protein binding to this type of metal group. We characterized the iron-sulfur cluster using inductively coupled plasma-atomic emission spectroscopy, absorbance spectroscopy, and electron paramagnetic resonance spectroscopy and found that it is an oxygen-sensitive [4Fe-4S](2+) cluster. Four highly conserved cysteine residues were shown to be required for coordinating the iron-sulfur cluster, and substitution of any of these Cys residues with Ser or Ala within the context of ? gpL abolished biological activity. These data imply that the intact iron-sulfur cluster is required for function. The presence of four conserved Cys residues in the C-terminal regions of very diverse gpL homologues suggest that utilization of an iron-sulfur cluster is a widespread feature of non-contractile tailed phages that infect Gram-negative bacteria. In addition, this is the first example of a viral structural protein that binds an iron-sulfur cluster.
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Robust surface state of intrinsic topological insulator Bi2Te2Se thin films: a first-principles study.
J Phys Condens Matter
PUBLISHED: 12-19-2011
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Bi(2)Te(2)Se, a ternary tetradymite compound, has recently been identified to be a three-dimensional topological insulator. In this paper, we theoretically study the electronic structures of bulk and thin films of Bi(2)Te(2)Se employing spin-orbit coupling (SOC) self-consistently with density-functional theory. It is found that SOC plays an important role in determining the electronic properties of Bi(2)Te(2)Se. A finite bandgap opens up in the surface states of Bi(2)Te(2)Se thin films due to the hybridization of the top and bottom surface states of films. The intrinsic Bi(2)Te(2)Se thin films of three or more quintuple layers exhibit a robust topological nature of electronic structure with the Fermi energy intersecting the Dirac cone of the surface states only once between time-reversal-invariant momenta. These characteristics of Bi(2)Te(2)Se are similar to the topological behavior of Bi(2)Te(3), promising a variety of potential applications in nanoelectronics and spintronics.
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catena-Poly[[bis-(acetato-?O)aqua-copper(II)]-?-5-(pyridin-3-yl)pyrimidine-?N:N].
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-08-2011
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In the title compound, [Cu(CH(3)CO(2))(2)(C(9)H(7)N(3))(H(2)O)](n), the Cu(II) ion is penta-coordinated in a square-pyramidal geometry. The N atoms of the two chelating symmetry-related 5-(pyridin-3-yl)pyrimidine ligands and the O atoms of the two monodentate acetate anions are nearly coplanar, with a mean deviation from the least-squares plane of 0.157?(2)?Å and the Cu(II) ion is displaced by 0.050?(3)?Å from this plane towards the apical water O atom. Bridging through the bis-monodentate 5-(pyridin-3-yl)pyrimidine ligand forms a one-dimensional coordination polymer extending parallel to [010]. In the crystal, O-H?O hydrogen bonds link the mol-ecules into a two-dimensional supra-molecular structure parallel to (100). The crystal studied was an inversion twin with a 0.57?(3):0.43?(3) domain ratio.
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Tetraaquabis[5-(3-pyridyl-?N)pyrimidine]zinc(II) bis(trifluoromethanesulfonate): a novel cationic complex and three-dimensional hydrogen-bonded network.
Acta Crystallogr C
PUBLISHED: 07-25-2011
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The title compound, [Zn(C(9)H(7)N(3))(2)(H(2)O)(4)](CF(3)O(3)S)(2), contains an octahedral [ZnL(2)(H(2)O)(4)](2+) cationic complex with trans geometry (Zn site symmetry -1), and each 5-(3-pyridyl)pyrimidine (L) ligand is coordinated in a monodentate fashion through the pyridine N atom. In the extended structure, these complexes, with both hydrogen-bond acceptor (pyrimidine) and donor (H(2)O) functions, are linked to each other by intermolecular water-pyrimidine O-H···N hydrogen-bonding interactions, resulting in a double chain along the crystallographic a axis. The trifluoromethanesulfonate anions are integrated into the chains via O-H···O hydrogen bonds between the coordinated water and sulfonate O atoms. These double chains are associated into a novel three-dimensional network through interchain water-pyrimidine O-H···N hydrogen bonds. The asymmetric ligand plays an important role in constructing this unusual supramolecular structure.
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Absorption of Pt clusters and the induced magnetic properties of graphene.
J Phys Condens Matter
PUBLISHED: 07-16-2010
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First-principles total energy calculations are performed to investigate the formation and structures of Pt clusters on graphene. It is found that the formation energy of Pt on graphene increases with increasing Pt coverage. The structures of the absorbed Pt are that it is at the bridge site for a single Pt atom absorption, but form a dimerized cluster when two atoms are absorbed on graphene. For three- and four-Pt-atom absorption, linear and tetrahedral structures form, respectively, and the three-dimensional tetrahedral Pt(4) cluster is most stable in all the configurations investigated. There is a strong interatomic interaction among Pt atoms and so they tend to form clusters. While no magnetic behavior is expected after a single Pt atom is absorbed on graphene, the absorption of tetrahedral Pt(4) leads to Fermi level shifting to the valence band and the spin waves of C atoms in graphene become asymmetric and so they exhibit magnetism. The magnetic properties can thus be tuned by Pt absorption on graphene. The ultimate aim is to apply it in catalytic activity and electronic devices.
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Abdominal separation in an adult male patient with acute abdominal pain.
World J. Gastroenterol.
PUBLISHED: 07-09-2010
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We report a male patient with prolonged post-prandial abdominal distension and a sudden onset of epigastric pain initially diagnosed as acute abdomen. The patient had no history of surgery. Physical examination revealed peritonitis and abdominal computed tomography scan showed upper abdominal mesentery intorsion. The patient then underwent surgical intervention. It was found that the descending mesocolon dorsal root was connected to the ascending colon and formed a membrane encapsulating the small intestine. The membrane also formed an orifice in the ileal pars caeca, from which a 30 cm herniated ileum formed a "C"-shaped loop which was strangulated by the orifice. An abdominal separation was diagnosed after surgery. We liberated the membranous peritoneum which incarcerated the intestinal canal from the root of ileocecal junction to Treitz ligament, and reduced the small intestinal malrotation. The patient had an uneventful recovery after operation with his abdominal distention disappeared during the follow-up. Abdominal separation is a rare situation, which may be related with embryo development. Surgery is a choice of treatment for it.
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Preparation and characterization of a monoclonal antibody with high affinity for soluble Abeta oligomers.
Hybridoma (Larchmt)
PUBLISHED: 10-28-2009
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Amyloid beta-protein (Abeta) has been causally implicated in the neurodegenerative processes that accompany Alzheimers disease. Soluble oligomers of the Abeta(1-42) fragment are thought to be significantly more neurotoxic than higher molecular weight aggregates. We report the isolation and characterization of a mouse monoclonal antibody (MAb) directed against soluble Abeta(1-42) oligomers. Synthetic Abeta(1-42) oligomers were assembled in vitro; these were used to immunize mice, and hybridomas were isolated following myeloma fusion of splenocytes from immunized animals. Screening for reactivity against Abeta(1-42) resulted in the identification of MAb A8 with high affinity for soluble oligomers. The isotype of A8 was found to be IgG(2b). Experiments using sub-peptides of Abeta(1-42) revealed that the epitope identified by A8 lies within the 1-6 region of Abeta. The antibody displays high affinity for soluble Abeta(1-42) oligomers in the molecular weight range of 16.5-25 kDa, and detected target antigen in brain sections from senescence-accelerated SAMP 8 mice. The sensitivity and optimal titers for the detection of soluble Abeta(1-42) oligomers were determined to be 0.625 microg/mL in indirect ELISA, and 1:10(6), 1:4000, and 1:150 for ELISA, Western blotting, and immunohistochemistry, respectively. The A8 antibody specific for soluble Abeta(1-42) oligomers will provide a valuable tool for Alzheimers disease research.
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Expression and clinical significance of tbx2 in pancreatic cancer.
Asian Pac. J. Cancer Prev.
PUBLISHED: 05-28-2009
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TBX2 is one of the family of genes encoding developmental transcription factors, characterized by a 200 amino acid DNA binding domain (T-box), found to be related to malignant phenotypes of mammary cancer. However, the role of TBX2 in pancreatic cancer progression remains unclear. Therefore, the present study was conducted to investigate the expression and clinical significance of TBX2 in pancreatic cancer. Immunohistochemistry was carried out on paraffin-embedded sections of pancreatic cancer and normal pancreatic tissues. In addition, semiquantitative RT-PCR and Western blots were carried out to analyze mRNA and protein expression of Tbx2 in 6 pairs of freshly resected pancreatic cancer and their adjacent nontumorous tissue. TBX2 expression was significantly increased in pancreatic cancer tissue (29/48 or 60.4%). The expression level of Tbx2 had a significant positive relationship with tumor differentiation degree, higher TNM stage and distant metastasis. Also, mRNA and protein expression of Tbx2 were found to be at higher levels in almost all cancer tissues compared to adjacent tissues. In conclusion, Tbx2 protein might play an important role in the process of the development and metastasis of pancreatic cancers and high-level Tbx2 expression might be related to malignant potential.
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Granulation of activated sludge in a pilot-scale sequencing batch reactor for the treatment of low-strength municipal wastewater.
Water Res.
PUBLISHED: 03-26-2009
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Aerobic granulation of activated sludge was achieved in a pilot-scale sequencing batch reactor (SBR) for the treatment of low-strength municipal wastewater (<200 mg L(-1) of COD, chemical oxygen demand). The volume exchange ratio and settling time of an SBR were found to be two key factors in the granulation of activated sludge grown on the low-strength municipal wastewater. After operation of 300 days, the mixed liquor suspended solids (MLSS) concentration in the SBR reached 9.5 g L(-1) and consisted of approximate 85% granular sludge. The average total COD removal efficiency kept at 90% and NH4+-N was almost completely depleted (approximately 95%) after the formation of aerobic granules. The granules (with a diameter over 0.212 mm) had a diameter ranging from 0.2 to 0.8 mm and had good settling ability with a settling velocity of 18-40 m h(-1). Three bacterial morphologies of rod, coccus and filament coexisted in the granules. Mathematical modeling was performed to get insight into this pilot-scale granule-based reactor. The modified IWA activated sludge model No 3 (ASM3) was able to adequately describe the pilot-scale SBR dynamics during its cyclic operation.
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Cloning and characterization of DULP, a novel ubiquitin-like molecule from human dendritic cells.
Cell. Mol. Immunol.
PUBLISHED: 03-04-2009
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We identified a novel ubiquitin-like molecule DULP from human dendritic cells. DULP contains a domain that shares 26% identity and 34% similarity with ubiquitin, and it possesses the corresponding Ile-44 hydrophobic patch used by mono- or poly-ubiquitin to interact with a ubiquitin-interaction motif (UIM) or ubiquitin-associated domain (UBA). Lysine residue corresponding to 6 of ubiquitin, which is involved in the formation of a multi-ubiquitin chain that can bind proteasomal subunit Rpn10/S5a, is also conserved in its ubiquitin-homology domain. However, DULP does not possess the highly conserved C-terminus Gly-Gly required for ubiquitin conjugation or the Lys-48 required for the formation of polyubiquitin chain to target substrates for degradation, suggesting it might be a novel ubiquitin-domain protein (UDP). DULP was found widely expressed in many cells and the ubiquitin-homology domain was not cleaved. We also confirmed that DULP expression was enriched in the nucleus and much weaker in the cytosol. Besides, we found that overexpression of DULP in 293T cells induced apoptosis, which might not be associated with the mitochondrial or proteasome pathway, with the specific mechanism remaining unclear. Further investigations are needed to identify the precise biological functions of DULP.
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A novel C-type lectin from the shrimp Litopenaeus vannamei possesses anti-white spot syndrome virus activity.
J. Virol.
PUBLISHED: 01-09-2009
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C-type lectins play key roles in pathogen recognition, innate immunity, and cell-cell interactions. Here, we report a new C-type lectin (C-type lectin 1) from the shrimp Litopenaeus vannamei (LvCTL1), which has activity against the white spot syndrome virus (WSSV). LvCTL1 is a 156-residue polypeptide containing a C-type carbohydrate recognition domain with an EPN (Glu(99)-Pro(100)-Asn(101)) motif that has a predicted ligand binding specificity for mannose. Reverse transcription-PCR analysis revealed that LvCTL1 mRNA was specifically expressed in the hepatopancreas of L. vannamei. Recombinant LvCTL1 (rLvCTL1) had hemagglutinating activity and ligand binding specificity for mannose and glucose. rLvCTL1 also had a strong affinity for WSSV and interacted with several envelope proteins of WSSV. Furthermore, we showed that the binding of rLvCTL1 to WSSV could protect shrimps from viral infection and prolong the survival of shrimps against WSSV infection. Our results suggest that LvCTL1 is a mannose-binding C-type lectin that binds to envelope proteins of WSSV to exert its antiviral activity. To our knowledge, this is the first report of a shrimp C-type lectin that has direct anti-WSSV activity.
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Obtaining cellulose binding and hydrolyzing activity of a family 11 hybrid xylanase by fusion with xylan binding domain.
Protein Expr. Purif.
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The xylan binding domain (XBD) and linker sequences (LS) from thermostable and thermophilic Thermomonospora fusca xylanase A (TfxA) was fused to the carboxyl-terminus of a family 11 hybrid xylanase ATx. The constructed chimera (ATxX) was successfully expressed in Pichia pastoris, partially purified to homogeneity, and then characterized in detail. After 96-h 0.25% methanol induction, the xylanase and cellulose activity of ATxX from pPATxX1 transformant culture medium supernatant were 452.1 U/mg and 19.3 U/mg, respectively. SDS-PAGE analysis revealed that the molecular mass of ATxX was about 33.01 kDa. 3.7% ATxX was bound after incubation with 1% microcrystal cellulose at 25 °C for 3 h, while the ATx did not show cellulose binding-hydrolyzing ability. These results suggested that ATx obtained cellulose binding and hydrolyzing ability by fusing with XBD and LS. Enzymatic studies showed that the temperature and pH optimum of the ATxX xylanase activity were 60 °C and pH 5.0, respectively, which were the same as that of ATx. The temperature and pH optimum of the ATxX cellulase activity were 60 °C and pH 6.0, respectively. The major hydrolytic products released by ATxX from birchwood xylan were xylotriose and xylohexaose. Xylooligosaccharides from xylobiose to xylohexaose could be hydrolyzed by ATxX. Mode of action analysis showed that the chimeric ATxX was an endo-acting enzyme. The XBD and LS plays an important role in the binding and hydrolyzing of xylanase to insoluble substrates.
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Toll-like receptor 9 is correlated to disease activity in Chinese systemic lupus erythematosus population.
Chin. Med. J.
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Toll like receptor (TLR) 9 has been shown to play a crucial role in the pathogenesis of systemic lupus erythematosus (SLE) in animal models. Its pathogenic role in human SLE, however, was poorly elucidated. This study was performed to investigate the role of TLR9 involved in the aberrant signaling pathway and its correlation with disease activity in SLE.
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[The analysis of Lebers hereditary optic neuropathy associated with mitochondrial tRNAAla C5601T mutation in seven Han Chinese families].
Yi Chuan
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We reported here the clinical, genetic, and molecular characterization of Lebers hereditary optic neuropathy (LHON) with C5601T mutation in seven Chinese families. The ophthalmologic examinations of seven Chinese families who were clinically diagnosed LHON were conducted. Strikingly, these families exhibited very low penetrance of visual impairment, and the penetrance was 9.5%, 14.3%, 4.5%, 8.3%, 10.0%, 22.2% and 25.0%. Meanwhile, entire mitochondrial genome of seven probands was amplified by PCR using 24 pairs of oligonucleotide primers with overlapping fragments. Molecular analysis of mitochondrial DNA (mtDNA) in these pedigrees revealed the absence of three common LHON associated G11778A, G3460A and T14484C mutations but the presence of homoplastic LHON associated tRNAAla C5601T mutation in probands and other matrilineal relatives. These mtDNA polymorphism sites belongs to the Asian haplogroups G2, G2a1, G2a1, G2, G2b, G2a1 and G2. By analyzing mitochondrial genome, seven LHON families all carry the C5601T mutation. The C5601T mutation occurs at the highly conserved nucleotide (conventional position 59) of tRNAAla, thereby contributing to the structural formation and stabilization of functional tRNAs and leading to mitochondrial dysfunction involved in visual impairment. The incomplete penetrance of visual loss in these seven Chinese pedigrees strongly indicates that the tRNAAla C5601T mutation was itself insufficient to produce a clinical phenotype. The lack of functional mtDNA variants in these pedigrees ruled out the role of mitochondrial background in the phenotypic expression of visual loss. Therefore, nuclear backgrounds and environmental factors seem to be modifying factors for the phenotypic manifestation of the tRNAAla C5601T mutation in the seven Chinese families.
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Nanoparticle-mediated local delivery of an antisense TGF-?1 construct inhibits intimal hyperplasia in autogenous vein grafts in rats.
PLoS ONE
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Intimal hyperplasia is one of the most important causes of vascular graft failure. Numerous studies have correlated transforming growth factor-?1 (TGF-?1) with extracellular matrix (ECM) deposition, a hallmark of intimal thickening.
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Eicosapentaenoic acid facilitates the folding of an outer membrane protein of the psychrotrophic bacterium, Shewanella livingstonensis Ac10.
Biochem. Biophys. Res. Commun.
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Polyunsaturated fatty acids, such as eicosapentaenoic acid (EPA), are found in various cold-adapted microorganisms. We previously demonstrated that EPA-containing phospholipids (EPA-PLs) synthesized by the psychrotrophic bacterium Shewanella livingstonensis Ac10 support cell division, membrane biogenesis, and the production of membrane proteins at low temperatures. In this article, we demonstrate the effects of EPA-PLs on the folding and conformational transition of Omp74, a major outer membrane cold-inducible protein in this bacterium. Omp74 from an EPA-less mutant migrated differently from that of the parent strain on SDS-polyacrylamide gel, suggesting that EPA-PLs affect the conformation of Omp74 in vivo. To examine the effects of EPA-PLs on Omp74 protein folding, in vitro refolding of recombinant Omp74 was carried out with liposomes composed of 1,2-dipalmitoleoyl-sn-glycero-3-phosphoglycerol and 1,2-dipalmitoleoyl-sn-glycero-3-phosphoethanolamine (1:1 molar ratio) with or without EPA-PLs as guest lipids. SDS-PAGE analysis of liposome-reconstituted Omp74 revealed more rapid folding in the presence of EPA-PLs. CD spectroscopy of Omp74 folding kinetics at 4 °C showed that EPA-PLs accelerated ?-sheet formation. These results suggest that EPA-PLs act as chemical chaperones, accelerating membrane insertion and secondary structure formation of Omp74 at low temperatures.
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What is Visualize?

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.