APOBEC-1 overexpression in liver has been shown to effectively reduce apoB-100 levels. However, nonspecific hypermutation and liver tumor formation potentially related to hypermutation in transgenic animals compromise its potential use for gene therapy. In studying apoB mRNA editing regulation, we found that the core editing auxiliary factor ACF dose-dependently increases APOBEC-1 nonspecific hypermutation and specific editing with variable site sensitivity.
View Article and Find Full Text PDFWe demonstrate controlled excitation of Bloch modes and manipulation of diffraction and refraction in optically induced two-dimensional photonic lattices. Solely by adjusting the bias condition, the lattice structures can be reconfigured at ease, enabling the observation of transition between Bloch modes associated with different high-symmetry points of a photonic band, and interplay between normal and anomalous diffraction as well as positive and negative refraction under identical excitation condition.
View Article and Find Full Text PDFCytochrome P450 sterol 14alpha-demethylases (CYP51s) are essential enzymes in sterol biosynthesis and well-known as the target of antifungal drugs. All fungal CYP51s are integral membrane proteins, making structural and biophysical characterization more challenging. The X-ray crystallographic structure of CYP51 isolated from Mycobacterium tuberculosis (MT-CYP51) is the unique reported one hitherto.
View Article and Find Full Text PDFSerum amyloid A (SAA) is a major acute phase protein involved in multiple physiological and pathological processes. This study provides experimental evidence that CD36, a phagocyte class B scavenger receptor, functions as a novel SAA receptor mediating SAA proinflammatory activity. The uptake of Alexa Fluor 488 SAA as well as of other well established CD36 ligands was increased 5-10-fold in HeLa cells stably transfected with CD36 when compared with mock-transfected cells.
View Article and Find Full Text PDFZhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
December 2009
Objective: To investigate whether the biomechanical effect of mushroom shaped surface prosthesis on femoral neck is in the scope of safety after the replacement.
Methods: Four donated fresh-adult specimens of upper femur under the age of 55 years old were used. The strains of detecting points A (lateral) and B (medial) on the narrow place of femoral neck in the standing position were simulated for three stages before or after the prosthesis replacement, namely the pre-replacement, the initial stage during which the interspace of the prosthesis was filled with cancellous bone, and later stage during which the interspace of the prosthesis was filled with bone cement.
Wurtzite structured zinc sulfide (ZnS) nanowire arrays are synthesized on silicon (111) wafers by a facile evaporation-condensation approach. These ZnS nanowire arrays possess predominant field emission properties with a low turn-on field of 2.9 V microm(-1), a low threshold field of 4.
View Article and Find Full Text PDFWe study nonlinear propagation of optical vortices in presence of hybrid nonlinearity as established in a nonconventional biased photorefractive crystal. Our results indicate that under hybrid nonlinearity the breakup of a singly-charged vortex along with the loss of its angular momentum is suppressed considerably as compared with that under conventional self-focusing or self-defocusing nonlinearity. Disintegration of a doubly-charged vortex under hybrid nonlinearity is also presented.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
August 2009
A simple method is demonstrated to synthesize high-quality cup-stacked carbon nanotubes (CSCNTs) with short length. The as-synthesized CSCNTs are 0.2-3.
View Article and Find Full Text PDFJ Nanosci Nanotechnol
November 2009
A series of Ti-Zr-O nanotube arrays on Ti-Zr alloys with different ratios of Ti to Zr were prepared by a simple anodization process, and their morphologies, crystal structures and optical properties were investigated. It is found that the morphology, length, crystal structure and optical properties of Ti-Zr-O tubes can be well controlled by adjusting the ratio of Ti to Zr in Ti-Zr alloys. The tubes obtained evolved from circa (ca.
View Article and Find Full Text PDFThe gradient-corrected density functional calculation is applied to search the lowest-energy configurations of Cu(n)N (n=1-6) clusters and the calculation indicated that Cu(3)N cluster is the most stable one. Based on the result, we further investigate the equilibrium geometries and stabilities of the Cu(3n)N(n) (n=2-5) clusters. We found that in Cu(6)N(2) cluster, N atoms formed a separate N(2) molecule away from the other part of the cluster.
View Article and Find Full Text PDFWe demonstrate self-trapping of light by simultaneously compensating normal and anomalous (saddle-shaped) diffractions with self-focusing and self-defocusing hybrid nonlinearity in optically induced ionic-type photonic lattices. Innovative two-dimensional gap solitons, named "saddle solitons," are established, whose phase and spectrum characteristics are different from all previously observed spatial solitons.
View Article and Find Full Text PDFFluorescence targeted imaging in vivo has proven useful in tumor recognition and drug delivery. In the process of in vivo imaging, however, a high autofluorescence background could mask the signals from the fluorescent probes. Herein, a high contrast upconversion luminescence (UCL) imaging protocol was developed for targeted imaging of tumors based on RGD-labeled upconversion nanophosphors (UCNPs) as luminescent labels.
View Article and Find Full Text PDFWe demonstrate tunable re-directing, blocking, and splitting of a light beam along defect channels based on spatial bandgap guidance in two-dimensional photonic lattices. We show the possibility for linear control of beam propagation and multicolor routing with specially designed junctions and surface structures embedded in otherwise uniform square lattices.
View Article and Find Full Text PDFWe demonstrate experimentally the formation of three-dimensional (3D) reconfigurable photonic lattices in a bulk nonlinear crystal by employing the optical induction technique. Such 3D lattices are established by inducing 2D square lattices in two orthogonal directions. The induced 3D periodic index structures are monitored by plane-wave guidance and Brillouin zone spectroscopy.
View Article and Find Full Text PDFSichuan Da Xue Xue Bao Yi Xue Ban
May 2009
Objective: To investigate the expression of endothelin-1 (ET-1) and its receptors (ET(A)R, ET(B)R) in patients with endometriosis and to explore the possible role of them in the pathogenesis of endometriosis.
Methods: The tissues of ectopic and eutopic endometrium were collected from 48 cases of endometriosis (EM), while the control samples were eutopic endometrium from 13 cases of cervical intraepithelial neoplasia (CIN). The expressions and locations of ET-1, ET(A)R, ET(B)R were measured by immunohistochemical staining.
Large scaled hexagonal prismatic sub-micro sized Mg crystals were grown by a vapor-liquid-solid process, and found to be sensitive to electron beam irradiation in transmission electron microscope imaging, making hollow prismatic MgO boxes.
View Article and Find Full Text PDFRare-earth up-converting nanophosphors (UCNPs) have great potential to become a new generation of biological luminescent labels, but their use has been limited by difficulties in obtaining water-soluble UCNPs bearing appropriate functional groups. To address this problem, we report herein a simple and efficient procedure for the preparation of amine-functionalized UCNPs by a modified hydrothermal microemulsion route assisted with 6-aminohexanoic acid. The amine content of the resultant UCNPs has been determined to be (9.
View Article and Find Full Text PDFCoupled ZnO/CdS heterostructures based on the Z-scheme mechanism are demonstrated to be highly active photocatalysts for H(2) evolution under simulated solar light irradiation due to the greatly prolonged lifetime of photoexcited carriers.
View Article and Find Full Text PDFFreestanding and flexible graphene/polyaniline composite paper was prepared by an in situ anodic electropolymerization of polyaniline film on graphene paper. This graphene-based composite paper electrode, consisting of graphene/polyaniline composite sheets as building blocks, shows a favorable tensile strength of 12.6 MPa and a stable large electrochemical capacitance (233 F g(-1) and 135 F cm(-3) for gravimetric and volumetric capacitances), which outperforms many other currently available carbon-based flexible electrodes and is hence particularly promising for flexible supercapacitors.
View Article and Find Full Text PDFWe provide what we believe to be the first experimental demonstration of linear Shockley-like surface states in an optically induced semi-infinite photonic superlattice. Such surface states appear only when the induced superlattice consisting of alternating strong and weak bonds is terminated properly at the surface. Our experimental results are in good agreement with our theoretical analysis.
View Article and Find Full Text PDFNitrogen doped mesoporous TiO(2) was prepared via a modified two-step hydrothermal route. In contrast to undoped mesoporous TiO(2), nitrogen doped mesoporous TiO(2) has superior photocatalytic activity under both UV and visible light irradiation. Photoluminescence spectra reveal that nitrogen doped mesoporous TiO(2) possesses abundant surface states, which can play a vital role in trapping photoinduced carriers as evidenced by photoelectrochemical process and prolonging the lifetime of the carriers.
View Article and Find Full Text PDFWe demonstrate selective excitation of soliton trains residing in different gaps or within the same Bloch band of a new type of photonic lattice merely by changing the orientation of an input probe beam. A self-focusing and -defocusing hybrid nonlinearity as established in a nonconventionally biased photorefractive crystal leads to controlled soliton transitions from different band edges or subband edges, in good agreement with our theoretical analysis.
View Article and Find Full Text PDFA simple method is described for efficient, asymmetric and coherent continuum generation in the mid-infrared region based on the dynamics of a stabilized soliton in the vicinity of a second dispersion zero of a nonlinear fiber. The mechanism involves nonlinear soliton compression, Raman self-frequency shift and resonant emission of a dispersive (Cherenkov) wave in a non-uniformly tapered ZBLAN fluoride fiber pumped by a low-power compact femtosecond laser at 1.55 microm.
View Article and Find Full Text PDFNitrogen-doped titania nanosheets with visible light response were synthesized by exfoliating a layered titanate with homogeneous nitrogen doping.
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