916 research outputs found
Tightly bound excitons in monolayer WSe2
Exciton binding energy and excited states in monolayers of tungsten
diselenide (WSe2) are investigated using the combined linear absorption and
two-photon photoluminescence excitation spectroscopy. The exciton binding
energy is determined to be 0.37eV, which is about an order of magnitude larger
than that in III-V semiconductor quantum wells and renders the exciton excited
states observable even at room temperature. The exciton excitation spectrum
with both experimentally determined one- and two-photon active states is
distinct from the simple two-dimensional (2D) hydrogenic model. This result
reveals significantly reduced and nonlocal dielectric screening of Coulomb
interactions in 2D semiconductors. The observed large exciton binding energy
will also have a significant impact on next-generation photonics and
optoelectronics applications based on 2D atomic crystals.Comment: 19 pages, 4 figures, to appear in PR
Anti-tumor effect of polysaccharides from rhizome of Curculigo orchioides Gaertn on cervical cancer
Purpose: To investigate the anti-tumor effects of polysaccharides from Curculigo orchioides (PDC) on cervical cancer and the possible mechanisms involved.Methods: A Box–Behnken design (BBD) was employed to optimize extraction conditions for PDC. The anti-tumor effect of PDC on cervical cancer was investigated in vivo in mice injected with Hela cells. The parameters measured were tumor volume and weight. In vitro anti-tumor effects of PDC were assessed by measuring expressions of caspase-3, caspase-9 and P53 proteins in Hela cells via ELISA assay. Thymus and spleen indices were calculated for assessment of PDC effect on immune function.Results: The optimum extraction conditions predicted by the response surface methodology (RSM) were: extraction time = 1.58 h, ratio-of-water-to-sample = 30.05 mL/g and extraction number = 1.95. PDC showed significant anti-tumor effect on cervical cancer in mice. It significantly increased thymus and spleen indices in mice; and significantly up-regulated expressions of caspase-3, caspase-9 and P53 proteins in HeLa cells.Conclusion: PDC has significant anti-tumor effect on cervical cancer in vivo and in vitro, most probably through mechanisms involving enhancement on immune function and induction of apoptosis.Keyword: Curculigo orchioides, Polysaccharides, Cervical cancer, HeLa cells, Apoptosi
2-Amino-4-[1-(2-chlorophenyl)-5-methyl-1H-1,2,3-triazol-4-yl]-6-(4-methylphenyl)benzene-1,3-dicarbonitrile
In the title compound, C24H17ClN6, the dihedral angles between the triazolyl ring and its adjacent chlorobenzene and trisubstituted benzene rings are 90.6 (2) and 55.7 (3)°, respectively. The dihedral angle between the trisubstituted ring and the attached tolyl ring of the biphenyl unit is 45.9 (3)°. Intra- and intermolecular N—H⋯N hydrogen bonds are present
High throughput 16SrRNA gene sequencing reveals the correlation between Propionibacterium acnes and sarcoidosis
Sequences of the unique OTUs. (XLS 3616Â kb
catena-Poly[[diaquacadmium(II)]bis(μ-pyridine-3-sulfonato)-κ2 N:O;κ2 O:N]
In the title polymeric complex, [Cd(C5H4NO3S)2(H2O)2]n, the Cd atom is located on a centre of inversion and is coordinated by two O atoms and two N atoms, derived from four different pyridine-3-sulfonate ligands, and two O atoms derived from two water molecules, forming a distorted trans-N2O4 octahedral geometry. The topology of the polymer is a one-dimensional chain mediated by bridging pyridine-3-sulfonate anions. These are connected into a three-dimensional architecture via hydrogen bonds
Overexpression of immunoglobulin G prompts cell proliferation and inhibits cell apoptosis in human urothelial carcinoma
Only B lymphocytes can express immunoglobulins according to the traditional immunological theories, and the expression of immunoglobulin G (IgG) messenger RNA (mRNA) and protein was found in certain human cancer cells recently. However, the expression pattern of IgG and its possible role in human urothelial carcinoma are still elusive. In this study, we investigated the expression of IgG in two human urothelial carcinoma cell lines, T24 and BIU-87, and in 56 cases of clinical urothelial carcinoma tissues. The mRNA of IgG was positively detected by in situ hybridization and reverse transcription PCR; furthermore, IgG protein was also positively detected by immunohistochemistry and Western blot. Moreover, blockade of tumor-derived IgG by either antihuman IgG antibody or antisense oligonucleotides increased cell apoptosis and inhibited cell growth in bladder cancer cell lines in vitro, and antihuman IgG antibody could suppress the growth of xenotransplant tumor in vivo. In addition, either antihuman IgG antibody or antisense oligonucleotides enhanced the sensitivity to mitomycin C in bladder cancer cell line T24. Furthermore, blockade of IgG in bladder cancer cell T24 resulted in upregulation of cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase. Our results indicated that bladder cancer cells were capable of expressing IgG, and blockade of IgG expression induced cell apoptosis through activation of caspase-dependent pathway. A novel potential targeted therapy for bladder cancer will be possibly developed based on these data. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s13277-013-0717-z) contains supplementary material, which is available to authorized users
catena-Poly[[diaquamanganese(II)]-di-μ-pyridine-3-sulfonato-κ2 N:O;κ2 O:N]
In the title polymeric complex, [Mn(C5H4NO3S)2(H2O)2]n, the Mn atom is located on a centre of inversion and is coordinated by two O atoms and two N atoms derived from four different pyridine-3-sulfonate (pySO3) ligands, and two O atoms derived from two water molecules in a distorted trans-N2O4 octahedral geometry. The metal atoms are bridged by the pySO3 ligands to form a one-dimensional chain. The chains are further connected into a three-dimensional architecture via hydrogen bonds
Comprehensive molecular diagnosis of 67 Chinese Usher syndrome probands: high rate of ethnicity specific mutations in Chinese USH patients
Both Novel missense alleles identified in MYO7A genes are conserved between human, zebrafish and Drosophila melanogaster. (PPTX 676 kb
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