Formation of helical organic-inorganic hybrid silica nanotubes using a chiral anionic gelator.

Right-handed helical organic-inorganic hybrid silica nanotubes were prepared using a chiral anionic gelator with 3-aminopropyltrimethoxysilane as a co-structure-directing agent and 1,4-bis(triethoxysilyl)benzene, 4,4'-bis(triethoxysilyl)-1,1'-biphenyl, bis(triethoxysilyl)methane, 1,2-bis(triethoxysilyl)ethane, and 1,2-bis(triethoxysilyl)ethene as the precursors. The sol-gel reactions were carried out in a mixture of water and ethanol at the volume ratio of 2.2:1.

[Polysomnographic study of bruxism in children].

Objective: To analyze the sleep electrophysiological changes and the sleep structure changes in children with bruxism by use of the polysomnography.

Methods: Twelve children with severe bruxism and 11 children who had no systemic diseases or sleep disorders were selected for polysomnography.

Results: The proportion of nonrapid eye movements sleep (NREMS)II and NREMS IV stages in bruxism group were (45.

Identification and characterization of maize microRNAs involved in the very early stage of seed germination.

Background: MicroRNAs (miRNAs) are a new class of endogenous small RNAs that play essential regulatory roles in plant growth, development and stress response. Extensive studies of miRNAs have been performed in model plants such as rice, Arabidopsis thaliana and other plants. However, the number of miRNAs discovered in maize is relatively low and little is known about miRNAs involved in the very early stage during seed germination.

Isatin-β-thiosemicarbazones as potent herpes simplex virus inhibitors.

A series of isatin-β-thiosemicarbazones have been designed and evaluated for antiviral activity against herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) in a plaque reduction assay. Their cytotoxicity was examined using human rhabdomyosarcoma cells (RD cells). Several derivatives of isatin-β-thiosemicarbazone exhibited significant and selective antiviral activity with low cytotoxicity.

Handedness inversion in preparing chiral 4, 4(')-biphenylene-silica nanostructures.

An anionic gelator, D-C12ValC10COONa, derived from D-valine can cause physical gels in water and organic solvents. Helical 4,4(')-biphenylene-silica nanotubes and nanoribbons were prepared using it with 3-aminopropyltrimethoxysilane as a co-structure-directing agent and 4,4(')-bis(triethoxysilyl)-1,1(')-biphenyl (BTESB) as precursor. It was found that the handedness of the hybrid silica nanotubes/nanoribbons is sensitive to the pH value and the concentration of the reaction mixtures.

Intra-family phenotypic heterogeneity of 16p11.2 deletion carriers in a three-generation Chinese family.

The 16p11.2 deletion is a recurrent genomic event and a significant risk factor for autism spectrum disorders (ASD). This genomic disorder also exhibits extensive phenotypic variability and diverse clinical phenotypes.

[Genetic and clinical study on 17 cases of Angelman syndrome with deletion of 15q11-13].

Objective: Angelman syndrome (AS) is a neurodevelopmental genetic disorder that maps to 15q11-13. The primary phenotypes are attributable to loss of expression of imprinted UBE3A gene within this region which can arise by means of a number of mechanisms. The purpose of this study was to make a genetic diagnosis and to analyze the clinical features in suspected patients with AS.

Identification of novel MLC1 mutations in Chinese patients with megalencephalic leukoencephalopathy with subcortical cysts (MLC).

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an autosomal, recessively inherited disease caused by mutations in the MLC1 gene. Most of the previously published studies have been carried out in ethnic populations other than the Chinese. In this study, the analysis of clinical features and MLC1 mutation screening were performed in 13 Chinese patients for the first time.

Assaying pharmacodynamic endpoints with targeted therapy: flavopiridol and 17AAG induced dephosphorylation of histone H1.5 in acute myeloid leukemia.

Histone H1 is commonly used to assay kinase activity in vitro. As many promising targeted therapies affect kinase activity of specific enzymes involved in cancer transformation, H1 phosphorylation can serve as potential pharmacodynamic marker for drug activity within the cell. In this study we utilized a phosphoproteomic workflow to characterize histone H1 phosphorylation changes associated with two targeted therapies in the Kasumi-1 acute myeloid leukemia cell line.

Design of a single-polarization single-mode photonic crystal fiber with a near-Gaussian mode field and wide bandwidth.

Single-polarization single-mode (SPSM) fiber can efficiently eliminate polarization mode coupling, polarization mode dispersion, and polarization-dependent loss. Up to now, most single-polarization fibers have been designed based on form birefringence, which would result in a non-Gaussian field distribution and a small effective mode field area. In this paper, a novel structure of SPSM photonic crystal fibers based on the resonant coupling phenomena is proposed and analyzed by using a full-vector finite-element method with a second-order transparent boundary condition.

[Progress in research on land cover products of MODIS].

Remote sensing technology has been rapidly developed in recent decades, and has been widely used in ecology and environment field. MODIS is a new data source, and in its many products, land cover product is an important product, and it has often been used in global and regional models. In the present review, the procedure of producing land cover product is clearly discussed, and the feature of the classification based network or decision tree is introduced.

Structural analysis of a highly glycosylated and unliganded gp120-based antigen using mass spectrometry.

Structural characterization of the HIV-1 envelope protein gp120 is very important for providing an understanding of the protein's immunogenicity and its binding to cell receptors. So far, the crystallographic structure of gp120 with an intact V3 loop (in the absence of a CD4 coreceptor or antibody) has not been determined. The third variable region (V3) of the gp120 is immunodominant and contains glycosylation signatures that are essential for coreceptor binding and entry of the virus into T-cells.

Synthesis, activity, and pharmacokinetic properties of a series of conformationally-restricted thiourea analogs as novel hepatitis C virus inhibitors.

A series of novel conformationally-restricted thiourea analogs were designed, synthesized, and evaluated for their anti-HCV activity. Herein we report the synthesis, structure-activity relationships (SARs), and pharmacokinetic properties of this new class of thiourea compounds that showed potent inhibitory activities against HCV in the cell-based subgenomic HCV replicon assay. Among compounds tested, the fluorene compound 4b was found to possess the most potent activity (EC(50)=0.

Modulation of microglial immune responses by a novel thiourea derivative.

Increasing evidence indicates that microglial activation plays an important role in the pathogenesis of Alzheimer's disease (AD). In AD, activated microglia may facilitate the clearance of beta-amyloid (Abeta), a neurotoxic component in AD pathogenesis. However, microglial activation comes at the cost of triggering neuro-inflammation, which contributes to cerebral dysfunction.

Submicroscopic subtelomeric aberrations in Chinese patients with unexplained developmental delay/mental retardation.

Background: Subtelomeric imbalance is widely accepted as related to developmental delay/mental retardation (DD/MR). Fine mapping of aberrations in gene-enriched subtelomeric regions provides essential clues for localizing critical regions, and provides a strategy for identifying new candidate genes. To date, no large-scale study has been conducted on subtelomeric aberrations in DD/MR patients in mainland China.

Association of oxidative stress with realgar-induced differentiation in human leukemia HL-60 cells.

Background: Realgar (arsenic sulfide, As(4)S(4)) has been shown to have clinical efficacy in patients with newly diagnosed and relapsed acute promyelocytic leukemia. Mechanistic studies have demonstrated that realgar is able to induce cell differentiation.

Methods: The oxidative stress in the realgar-induced differentiation was examined with human leukemia HL-60 cells.

Design and efficient synthesis of novel arylthiourea derivatives as potent hepatitis C virus inhibitors.

A novel class of arylthiourea HCV inhibitors bearing various functionalities, such as cyclic urea, cyclic thiourea, urea, and thiourea, on the alkyl linker were designed and synthesized. Herein we report the synthesis and structure-activity relationships (SARs) of this novel class of arylthiourea derivatives that showed potent inhibitory activities against HCV in the cell-based subgenomic HCV replicon assay. Among compounds tested, the new carbazole derivative 64, which has an eight-carbon linkage between the phenyl and carbazole rings and a tolyl group at the N-9 position of carbazole, was found to possess strong anti-HCV activity (EC50=0.

Lanthanum suppresses osteoblastic differentiation via pertussis toxin-sensitive G protein signaling in rat vascular smooth muscle cells.

A major cellular event in vascular calcification is the phenotypic transformation of vascular smooth muscle cells (VSMCs) into osteoblast-like cells. After demonstrating that lanthanum chloride (LaCl(3)) suppresses hydrogen peroxide-enhanced calcification in rat calcifying vascular cells (CVCs), here we report its effect on the osteoblastic differentiation of rat VSMCs, a process leading to the formation of CVCs. Cells were isolated from aortic media of male SD rats, and passages between three and eight were cultured in Dulbeccol's Modified Eagle's Medium (DMEM) containing 10% fetal bovine serum (FBS) and 10 mM beta-glycerophosphate (beta-GP) in the presence or absence of LaCl(3).

Histological studies on the telencephalon of Hynobius leechii at the metamorphosis phase and the adult phase.

Objective: To investigate the telencephalon developmental characteristics of Hynobius leehii, and enrich the research data of comparable neurobiology and nervous system development of amphibian.

Methods: HE staining and Nissl staining methods were used to study the telencephalon histological structure of Hynobius leechii at both the metamorphosis and the adult phases, and to explore the developmental phases of telencephalon.

Results: The olfactory bulb could be roughly divided into 6 layers from lateral to medial.

Design and synthesis of indole, 2,3-dihydro-indole, and 3,4-dihydro-2H-quinoline-1-carbothioic acid amide derivatives as novel HCV inhibitors.

An efficient synthetic methodology to provide indole, 2,3-dihydro-indole, and 3,4-dihydro-2H-quinoline-1-carbothioic acid amide derivatives is described. These conformationally restricted heterobicyclic scaffolds were evaluated as a novel class of HCV inhibitors. Introduction of an acyl group at the NH(2) of the thiourea moiety has been found to enhance inhibitory activity.

Directed evolution of an enantioselective epoxide hydrolase: uncovering the source of enantioselectivity at each evolutionary stage.

Directed evolution of enzymes as enantioselective catalysts in organic chemistry is an alternative to traditional asymmetric catalysis using chiral transition-metal complexes or organocatalysts, the different approaches often being complementary. Moreover, directed evolution studies allow us to learn more about how enzymes perform mechanistically. The present study concerns a previously evolved highly enantioselective mutant of the epoxide hydrolase from Aspergillus niger in the hydrolytic kinetic resolution of racemic glycidyl phenyl ether.

A hierarchical MS2/MS3 database search algorithm for automated analysis of phosphopeptide tandem mass spectra.

A novel hierarchical MS(2)/MS(3) database search algorithm has been developed to analyze MS(2)/MS(3) phosphopeptides proteomic data. The algorithm is incorporated in an automated database search program, MassMatrix. The algorithm matches experimental MS(2) spectra against a supplied protein database to determine candidate peptide matches.

Design, synthesis, and anti-HCV activity of thiourea compounds.

A series of thiourea derivatives were synthesized and their antiviral activity was evaluated in a cell-based HCV subgenomic replicon assay. SAR studies revealed that the chain length and the position of the alkyl linker largely influenced the in vitro anti-HCV activity of this class of potent antiviral agents. Among this series of compounds synthesized, the thiourea derivative with a six-carbon alkyl linker at the meta-position of the central phenyl ring (10) was identified as the most potent anti-HCV inhibitor (EC(50) = 0.

[Analysis of vegetation dynamics over Liaoning province based on remote sensing data].

In the present paper, the authors used normalized difference vegetation index (NDVI) data derived from NOAA AVHRR sensor to analyze spatial heterogeneity and temporal dynamics of Liaoning province during the past two decades. A set of 2 292 spatially distributed NDVI values were analyzed to investigate obvious deviations by the mean-monthly values from 1982 to 2001. Various statistical analyses including minimum, mean and maximum values, coefficient of variation (CV), standardized anomalies (Z-scores), and 36-month running mean were used for monthly NDVI values to research spatial and temporal variations in vegetation.