Thermo-responsive diblock copolymer, poly(-isopropylacrylamide)--poly(-vinylisobutyramide) was synthesized via switchable reversible addition-fragmentation chain transfer (RAFT) polymerization and its thermal transition behavior was studied. Poly(-vinylisobutyramide) (PNVIBA), a structural isomer of poly(-isopropylacrylamide) (PNIPAM) shows a thermo-response character but with a higher lower critical solution temperature (LCST) than PNIPAM. The chain extension of the PNVIBA block from the PNIPAM block proceeded in a controlled manner with a switchable chain transfer reagent, methyl 2-[methyl(4-pyridinyl)carbamothioylthio]propionate.
View Article and Find Full Text PDFAllele-specific expression quantification from RNA-seq reads provides opportunities to study the control of gene regulatory networks by -acting and -acting genetic variants. Many existing methods performed a single-gene and single-SNP association analysis to identify expression quantitative trait loci (eQTLs), and placed the eQTLs against known gene networks for functional interpretation. Instead, we view eQTL data as a capture of the effects of perturbation of gene regulatory system by a large number of genetic variants and reconstruct a gene network perturbed by eQTLs.
View Article and Find Full Text PDFObjective: Accurate motor timing is critical for efficient motor control of behaviors; however, the effect of motor timing abilities on movement-related neural activities has rarely been investigated. The current study aimed to examine the electrophysiological correlates of motor timing errors.
Methods: Twenty-two healthy volunteers performed motor timing tasks while their electroencephalographic and electromyographic (EMG) activities were simultaneously recorded.
Genetic variability can modulate individual drug responses. A significant portion of pharmacogenetic variants reside in the noncoding genome yet it is unclear if the noncoding variants directly influence protein function and expression or are present on a haplotype including a functionally relevant genetic variation (synthetic association). Gene-wise variant burden (GVB) is a gene-level measure of deleteriousness, reflecting the cumulative effects of deleterious coding variants, predicted in silico.
View Article and Find Full Text PDFCiliary neurotrophic factor (CNTF) promotes survival and enhances long-distance regeneration of injured axons in parts of the adult CNS. Here we tested whether CNTF gene therapy targeting corticospinal neurons (CSN) in motor-related regions of the cerebral cortex promotes plasticity and regrowth of axons projecting into the female adult F344 rat spinal cord after moderate thoracic (T10) contusion injury (SCI). Cortical neurons were transduced with a bitronic adeno-associated viral vector (AAV1) expressing a secretory form of CNTF coupled to mCHERRY (AAV-CNTF) or with control AAV only (AAV-GFP) two weeks prior to SCI.
View Article and Find Full Text PDFObjectives: Major public high-throughput functional genomic data repositories, including the Gene Expression Omnibus (GEO) and ArrayExpress have rapidly expanded. As a result, a large number of diverse high-throughput functional genomic data retrieval systems have been developed. However, high-throughput functional genomic data retrieval remains challenging.
View Article and Find Full Text PDFJ Colloid Interface Sci
February 2016
We explore plasmon coupling between silver nanoparticles (AgNPs) as two AgNPs approach each other within a subnanometer distance. We prepare AgNP dimers with two 21-nm AgNPs separated by alkanedithiol linkers in high yield. Changing the length of the alkanedithiol linkers enables us to control the interparticle distance down to the subnanometer level on the molecular scale.
View Article and Find Full Text PDFNoble metal nanoparticles (NPs) are the most commonly employed plasmonic substrates in surface-enhanced Raman scattering (SERS) experiments. Computer simulations show that monomers of Ag and Au nanocrystals ("spherical" NPs) do not exhibit a notable plasmonic enhancement, i.e.
View Article and Find Full Text PDFA variety of neurotrophic factors have been used in attempts to improve morphological and behavioural outcomes after experimental spinal cord injury (SCI). Here we review many of these factors, their cellular targets, and their therapeutic impact on spinal cord repair in different, primarily rodent, models of SCI. A majority of studies report favourable outcomes but results are by no means consistent, thus a major aim of this review is to consider how best to apply neurotrophic factors after SCI to optimize their therapeutic potential.
View Article and Find Full Text PDFThe assembly of noble metal nanoparticles is an appealing means to control the plasmonic properties of nanostructures. Dimers are particularly interesting because they are a model system that can provide fundamental insights into the interactions between nanoparticles in close proximity. Here, we report a highly efficient and facile assembly method for dimers and other forms of assemblies.
View Article and Find Full Text PDFUnderstanding molecular interactions at the interfaces of nanoparticles is fundamentally important because they determine the stability, affinity, functionality, and assembly of nanoparticles. However, probing the governing intermolecular forces at the interfaces, particularly for the nanoparticles dispersed in solution, remains challenging. Here, we demonstrate that the interfacial interactions between citrate-capped gold nanoparticles and various molecular functional groups can be probed using a plasmon ruler, based on a well-defined core-satellite nanoassembly structure.
View Article and Find Full Text PDFUnderstanding plasmon coupling between compositionally heterogeneous nanoparticles in close proximity is intriguing and fundamentally important because of the energy mismatch between the localized surface plasmons of the associated nanoparticles and interactions beyond classical electrodynamics. In this Letter, we explore surface plasmon coupling between silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs), assembled in the form of core-satellite structures. A recently developed assembly method allows us to prepare ultrapure core-satellite nanoassemblies in solution, where 50 nm AgNPs are surrounded by 13 nm AuNPs via alkanedithiol linkers.
View Article and Find Full Text PDFThe assembly of noble metal nanoparticles offers an appealing means to control and enhance the plasmonic properties of nanostructures. However, making nanoassemblies with easily modifiable gap distances with high efficiency has been challenging. Here, we report a novel strategy to assemble gold nanoparticles (AuNPs) into Janus-type asymmetric core-satellite nanostructures.
View Article and Find Full Text PDFThe measured concentrations of polybrominated diphenyl ethers (PBDEs) in inland sediments, from mono- to deca-BDE congeners, ranged from 0.46 to 1760 ng/g dry weight (dw) with mean and median values of 55±230 ng/g dw and 12 ng/g dw, respectively. These concentrations were comparable to or lower than those reported in other countries.
View Article and Find Full Text PDFCalcaneal fracture is the most common fracture in the tarsal bones. Treatment is difficult because the patterns of fracture are various and complications occur frequently. The purpose of this study was to evaluate the clinical results of calcaneal reconstruction for chronic complications after calcaneal fracture.
View Article and Find Full Text PDFPhys Chem Chem Phys
July 2011
Photoisomerization is an important reaction that confers photoresponsive functionality on nanoparticles. Although photoisomerization of molecules forming self-assembled monolayers on two-dimensional surfaces or three-dimensional clusters has been studied, a detailed picture of interactions of molecules undergoing isomerization with nanoparticles is not available. In this paper, we report on the photoisomerization of azobenzene derivatives spatially confined in gold nanoparticle (AuNP) aggregates.
View Article and Find Full Text PDFControlling the assembly of the nanoparticles is important because the optical properties of noble metal nanoparticles, such as the surface plasmon resonance (SPR) and surface-enhanced Raman scattering (SERS), are critically dependent on interparticle distances. Among many approaches available, light-induced disassembly is particularly attractive because it enables spatial modification of the optical properties of nanoparticle assemblies. In this study, we prepare gold nanoparticle (AuNP) aggregates in a gel matrix.
View Article and Find Full Text PDFDisulfide bonds play an important role in determining the structure and stability of proteins and nanoparticles. Despite extensive studies on the oxidation of thiols for the synthesis of disulfides, little is known about the photooxidation of thiols, which may be a clean, safe, and economical alternative to the use of harmful and expensive metal-containing oxidants and catalysts. In this paper, we report the photooxidative coupling of thiophenol derivatives to disulfides.
View Article and Find Full Text PDFWe report the time- and symmetry-dependent surface-enhanced Raman scattering (SERS) of gold nanoparticle (AuNP) aggregates. The addition of p-aminothiophenol (p-ATP) instantly induces the aggregation of AuNPs, confirmed by large absorption in the near-IR region. Dynamic light scattering measurements show that the addition of p-ATP immediately assembles the AuNPs (13 nm) to form aggregates with a mean diameter of approximately 200 nm, which then further grow to a size of approximately 300 nm.
View Article and Find Full Text PDFPurpose: To report the experiences at our institute of pars plana vitrectomy (PPV) in combination with intravitreal triamcinolone acetonide (IVTA) injection in patients with retained lens material after cataract surgery.
Methods: The medical records of patients who underwent PPV between January 2005 and December 2006 after complicated cataract surgery in which lens material was dropped into the vitreous cavity were reviewed retrospectively.
Results: Five eyes of five patients were treated by vitrectomy and removal of the dislocated lens material and were administered an adjuvant intravitreal injection of 4 mg triamcinolone acetonide at the end of surgery.
The contamination status of twelve persistent organic pollutants (POPs) on the Stockholm convention in the surface sediments of Han river, which is one of the largest river in the South Korea were investigated. Five organochlorine pesticides (OCPs) such as aldrin, dieldrin, endrin, mirex, and SigmaCHLs (alpha-chlordane, gamma-chlordane, cis-nonachlor, trans-nonachlor, and heptachlor) were not detected in all sediment samples. The overall concentrations of DDTs, HCB, dioxin-like PCBs (DL-PCBs) and PCDD/Fs were in the range of 1.
View Article and Find Full Text PDFWe reviewed the medical records of patients with acute retinal artery obstruction (RAO) and evaluated the importance of transthoracic echocardiography (TTE) and carotid Doppler ultrasound in determining causes of cardiac and carotid artery origin in RAO. A retrospective case study conducted in the Department of Ophthalmology, Inha University Hospital, Korea comprised 26 patients presenting with acute RAO who underwent systemic evaluation, TTE and carotid Doppler ultrasound between June 1, 1997 and December 31, 2003. Among these 26 patients, abnormal cardiac findings were detected in 12 (46%) and abnormal carotid findings in 4 (15%).
View Article and Find Full Text PDF