China National Center for Biotechnology Development

If the cap fits: Attachment of collagen (Col) to silica nanoparticles (MSN) by a disulfide linker, followed by introduction of lactobionic acid (LA, a cell-specific targeting moiety), results in a redox-responsive system for cell-specific intracellular drug delivery and efficient endocytosis (see picture). Controlled release of a model drug (fluorescein isothiocyanate, FITC) was achieved by cleavage of the disufide bonds. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

A multiwalled carbon nanotube/sulfur (MWCNT@S) composite with core-shell structure was successfully embedded into the interlay galleries of graphene sheets (GS) through a facile two-step assembly process. Scanning and transmission electron microscopy images reveal a 3D hierarchical sandwich-type architecture of the composite GS-MWCNT@S. The thickness of the S layer on the MWCNTs is ~20 nm. Raman spectroscopy, X-ray diffraction, thermogravimetric analysis, and energy-dispersive X-ray analysis confirm that the sulfur in the composite is highly crystalline with a mass loading up to 70% of the composite. This composite is evaluated as a cathode material for Li/S batteries. The GS-MWCNT@S composite exhibits a high initial capacity of 1396 mAh/g at a current density of 0.2C (1C = 1672 mA/g), corresponding to 83% usage of the sulfur active material. Much improved cycling stability and rate capability are achieved for the GS-MWCNT@S composite cathode compared with the composite lacking GS or MWCNT. The superior electrochemical performance of the GS-MWCNT@S composite is mainly attributed to the synergistic effects of GS and MWCNTs, which provide a 3D conductive network for electron transfer, open channels for ion diffusion, strong confinement of soluble polysulfides, and effective buffer for volume expansion of the S cathode during discharge.

Li excess LiNi0.8Co0.1Mn0.1O2 was produced by sintering the Ni0.8Co0.1Mn0.1(OH)2 precursor with different amounts of a lithium source. X-ray photoelectron spectroscopy confirmed that a greater excess of Li(+) leads to an increase in the number of Ni(2+) ions. Interestingly, the level of Li(+)/Ni(2+) disordering decreases with an increase in Ni(2+) content determined by the I003/I104 ratio in the X-ray diffraction patterns. The electrochemical measurement shows that the cycling stability and rate capability improve with an increase in Ni(2+) content. After cycling, electrochemical impedance spectroscopy shows decreased charge transfer resistance, and the XRD patterns exhibit an increased I003/I104 ratio with an increase in Ni(2+) content, reflecting the decrease in the level of Li(+)/Ni(2+) disorder during cycling.

To investigate the influence of surface-functionalized substrates with nanostructures on the behaviors of mesenchymal stem cells, we conjugated bone morphogenetic protein 2 (BMP2) onto TiO(2) nanotubes with different diameter sizes of 30, 60, and 100 nm for in vitro study. Polydopamine was employed as the intermediate layer for the conjugation of BMP2. The successful conjugation of BMP2 onto TiO(2) nanotubes was revealed by field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. Immunofluorescence staining of vinculin, osteocalcin (OCN), and osteopontin (OPN) revealed that BMP2-functionalized TiO(2) nanotubes was favorable for cell growth. More importantly, MSCs cultured onto BMP2-functionalized TiO(2) nanotubes displayed significantly higher (p < 0.05 or p < 0.01) differentiation levels of ALP and mineralization after 7 and 14 day cultures, respectively. The results suggested that surface functionalization of TiO(2) nanotubes with BMP2 was beneficial for cell proliferation and differentiation. The approach presented here has potential application for the development of titanium-based implants for enhanced bone osseointegration.

Abstract Background Panax notoginseng (Burk) F.H. Chen is important medicinal plant of the Araliacease family. Triterpene saponins are the bioactive constituents in P. notoginseng . However, available genomic information regarding this plant is limited. Moreover, details of triterpene saponin biosynthesis in the Panax species are largely unknown. Results Using the 454 pyrosequencing technology, a one-quarter GS FLX titanium run resulted in 188,185 reads with an average length of 410 bases for P. notoginseng root. These reads were processed and assembled by 454 GS De Novo Assembler software into 30,852 unique sequences. A total of 70.2% of unique sequences were annotated by Basic Local Alignment Search Tool (BLAST) similarity searches against public sequence databases. The Kyoto Encyclopedia of Genes and Genomes (KEGG) assignment discovered 41 unique sequences representing 11 genes involved in triterpene saponin backbone biosynthesis in the 454-EST dataset. In particular, the transcript encoding dammarenediol synthase (DS), which is the first committed enzyme in the biosynthetic pathway of major triterpene saponins, is highly expressed in the root of four-year-old P. notoginseng . It is worth emphasizing that the candidate cytochrome P450 (Pn02132 and Pn00158) and UDP-glycosyltransferase (Pn00082) gene most likely to be involved in hydroxylation or glycosylation of aglycones for triterpene saponin biosynthesis were discovered from 174 cytochrome P450s and 242 glycosyltransferases by phylogenetic analysis, respectively. Putative transcription factors were detected in 906 unique sequences, including Myb, homeobox, WRKY, basic helix-loop-helix (bHLH), and other family proteins. Additionally, a total of 2,772 simple sequence repeat (SSR) were identified from 2,361 unique sequences, of which, di-nucleotide motifs were the most abundant motif. Conclusion This study is the first to present a large-scale EST dataset for P. notoginseng root acquired by next-generation sequencing (NGS) technology. The candidate genes involved in triterpene saponin biosynthesis, including the putative CYP450s and UGTs, were obtained in this study. Additionally, the identification of SSRs provided plenty of genetic makers for molecular breeding and genetics applications in this species. These data will provide information on gene discovery, transcriptional regulation and marker-assisted selection for P. notoginseng . The dataset establishes an important foundation for the study with the purpose of ensuring adequate drug resources for this species.

BACKGROUND: Large-scale partial sequencing of cDNA libraries to generate expressed sequence tags (ESTs) is an effective means of discovering novel genes and characterizing transcription patterns in different tissues. To catalogue the identities and expression levels of genes in the cardiovascular system, we initiated large-scale sequencing and analysis of human cardiac cDNA libraries. METHODS AND RESULTS: Using automated DNA sequencing, we generated 43,285 ESTs from human heart cDNA libraries. An additional 41,619 ESTs were retrieved from public databases, for a total of 84,904 ESTs representing more than 26 million nucleotides of raw cDNA sequence data from 13 independent cardiovascular system-based cDNA libraries. Of these, 55% matched to known genes in the Genbank/EMBL/DDBJ databases, 33% matched only to other ESTs, and 12% did not match to any known sequences (designated cardiovascular system-based ESTs, or CVbESTs). ESTs that matched to known genes were classified according to function, allowing for detection of differences in general transcription patterns between various tissues and developmental stages of the cardiovascular system. In silico Northern analysis of known gene matches identified widely expressed cardiovascular genes as well as genes putatively exhibiting greater tissue specificity or developmental stage specificity. More detailed analysis identified 48 genes potentially overexpressed in cardiac hypertrophy, at least 10 of which were previously documented as differentially expressed. Computer-based chromosomal localizations of 1048 cardiac ESTs were performed to further assist in the search for disease-related genes. CONCLUSIONS: These data represent the most extensive compilation of cardiovascular gene expression information to date. They further demonstrate the untapped potential of genome research for investigating questions related to cardiovascular biology and represent a first-generation genome-based resource for molecular cardiovascular medicine.

Lactate and ammonia are the two major waste products formed during mammalian cell growth. Accumulation of these side products can have a negative effect on cell growth, and has drawn recent attention because of their inhibitory effects on the specific product synthesis rate. Our aim is to reduce lactate formation in the cell culture by genetically manipulating of the pathway of lactate synthesis with an aim to achieve high monoclonal antibody production. We have partially disrupted the LDH-A gene by homologous recombination in hybridoma cells (ATCC-CRL-1606). The cells that received the newly introduced DNA were selected by G418, and an LDH-deficient cell was identified by a screening method based on medium color changing in 96-well plates. A variant cell, LDH-neo21, was identified through this screening method and was characterized. The specific productivity of lactate by LDH-neo21 cells was 50% lower than that of parental cells. Intracellular LDH enzyme activity was significantly reduced. The cell growth was improved both in terms of cell density and cell viability. Total cell density potentially reached 5 x 10(6) cells/mL while the parental hybridoma cells had a cell density of 3.5 x 10(6) cells/mL, which represented a 30% increase. The antibody production of LDH-neo21 cells was threefold greater than that of parental cells during 5-day batch culture. Polymerase chain reaction (PCR) results showed that at least one copy of the LDH-A gene was disrupted in the LDH-neo21 cells. The variant of the hybridoma cell exhibited a significant advantage of reduced lactate formation in the cell culture with a high concentration of glucose, which led to a higher production of monoclonal antibody. 2001 John Wiley & Sons, Inc.

The tooth root is an important part of the tooth that works together with the surrounding periodontium to maintain the tooth in the alveolar socket. The root develops after crown morphogenesis. While the molecular and cellular mechanisms of early tooth development and crown morphogenesis have been extensively studied, little is known about the molecular mechanisms controlling tooth root formation. Here, we show that β-catenin is strongly expressed in odontoblast-lineage cells and is required for root formation. Tissue-specific inactivation of β-catenin in developing odontoblasts produced molars lacking roots and aberrantly thin incisors. At the beginning of root formation in the mutant molars, the cervical loop epithelium extended apically to form Hertwig's epithelial root sheath (HERS), but root odontoblast differentiation was disrupted and followed by the loss of some HERS inner layer cells. However, the outer layer of the HERS extended without the root, and the mutant molars finally erupted. The periodontal tissues extensively invaded the dental pulp. These results indicate that there is a cell-autonomous requirement for Wnt/β-catenin signaling in the dental mesenchyme for root formation.

The promising layered lithium-rich cathode materials, Li1.2Mn0.6−xNi0.2YxO2 (0 ≤ x ≤ 0.05), have been synthesized by substituting Mn4+ in Li1.2Mn0.6Ni0.2O2 with unusually large Y3+ ions, in order to improve their cycling performance and rate capability. An oxalate co-precipitation method is adopted in the synthetic process. X-ray diffraction (XRD) patterns show that, other than as a dopant, the yttrium element is found to become Y2O3 or LiYO2 in excess Y3+-doped samples. The effects of yttrium content on the electrochemical properties of the lithium-rich materials are investigated by electrochemical impedance spectroscopy (EIS) and galvanostatic charge–discharge tests as well. It demonstrates that the high capacity retention (240.7 mA h g−1 after 40 cycles at 0.1 C rate) and superior rate capability (184.5 mA h g−1 after 40 cycles at 1 C rate) have been achieved by the lithium-rich materials with a suitable amount of Y3+ doping. The “super-large” Y3+ can expand Li+-diffusing channels in the layered structure and stabilize the material structure.

MOTIVATION: The increasing availability of complete genome sequences provides excellent opportunity for the further development of tools for functional studies in proteomics. Several experimental approaches and in silico algorithms have been developed to cluster proteins into networks of biological significance that may provide new biological insights, especially into understanding the functions of many uncharacterized proteins. Among these methods, the phylogenetic profiles method has been widely used to predict protein-protein interactions. It involves the selection of reference organisms and identification of homologous proteins. Up to now, no published report has systematically studied the effects of the reference genome selection and the identification of homologous proteins upon the accuracy of this method. RESULTS: In this study, we optimized the phylogenetic profiles method by integrating phylogenetic relationships among reference organisms and sequence homology information to improve prediction accuracy. Our results revealed that the selection of the reference organisms set and the criteria for homology identification significantly are two critical factors for the prediction accuracy of this method. Our refined phylogenetic profiles method shows greater performance and potentially provides more reliable functional linkages compared with previous methods.

-AG was mainly through the ion exchange of hydroxyl groups. This study provides the possibility of synthesis of an efficient adsorbent by reusing the "waste", such as spent Li-ion batteries. It is an economic and environmentally friendly approach for both heavy-metal-contaminated water treatment and waste recycling.

A novel approach was used to prepare engineered biochar from biofuel residue (stillage from bagasse ethanol production) through slow pyrolysis. The obtained biochar was characterized for its physicochemical properties as well as silver sorption ability. Sorption experimental data showed that engineered biochar quickly and efficiently removed silver ion (Ag(+)) from aqueous solutions with a Langmuir maximum capacity of 90.06 mg/g. The high sorption of Ag(+) onto the biochar was attributed to both reduction and surface adsorption mechanisms. The reduction of Ag(+) by the biochar was confirmed with scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses of the postsorption biochar, which clearly showed the presence of metallic silver nanoparticles on the surface of the carbon matrix. An antimicrobial ability test indicated that silver-laden biochar effectively inhibited the growth of Escherichia coli, while the original biochar without silver nanoparticles promoted growth. Thus, biochar, prepared from biofuel residue materials, could be potentially applied not only to remove Ag(+) from aqueous solutions but also to produce a new value-added nanocomposite with antibacterial ability.

Phosphorus in water eutrophication has become a serious problem threatening the environment. However, the development of efficient adsorbents for phosphate removal from water is lagging. In this work, we recovered the waste material, graphitized carbon, from spent lithium ion batteries and modified it with nanostructured Mg(OH)2 on the surface to treat excess phosphate. This phosphate adsorbent shows one of the highest phosphate adsorption capacities to date, 588.4 mg/g (1 order of magnitude higher than previously reported carbon-based adsorbents), and exhibits decent stability. A heterogeneous multilayer adsorption mechanism was proposed on the basis of multiple adsorption results. This highly efficient adsorbent from spent Li-ion batteries displays great potential to be utilized in industry, and the mechanism study paved a way for further design of the adsorbent for phosphate adsorption.

Lignans, which are widely distributed in higher plants, represent a vast and rather diverse group of phenylpropane derivatives. They have attracted considerable attention due to their pharmacological activities. Some of the lignans have been developed approved therapeutics, and others are considered as lead structures for new drugs. This article is based on our previous review of lignans discovered in the period 2000-2004, and it provides a comprehensive compilation of the 354 new naturally occurring lignans obtained from 61 plant families between 2005 and 2011. We classified five main types according to their structural features, and provided the details of their sources, some typical structures, and diverse biological activities. A tabular compilation of the novel lignans by species is presented at the end. A total of 144 references were considered for this review.

BACKGROUND: The aberrant expression of microRNAs has been demonstrated to play a crucial role in the initiation and progression of hepatocarcinoma. miR-1246 expression in High invasive ability cell line than significantly higher than that in low invasive ability cell line. METHODS: Transwell chambers (8-uM pore size; Costar) were used in the in vitro migration and invison anssay. Dual luciferase reporter gene construct and Dual luciferase reporter assay to identify the target of miR-1246. CADM1 expression was evaluated by immunohistochemistric staining. The clinical manifestations, treatments and survival were collected for statistical analysis. RESULTS: Inhibition of miR-1246 effectively reduced migration and invasion of hepatocellular carcinoma cell lines. Bioinformatics and luciferase reporter assay revealed that miR-1246 specifically targeted the 3'-UTR of Cell adhesion molecule 1 and regulated its expression. Down-regulation of CADM1 enhanced migration and invasion of HCC cell lines. Furthermore, in tumor tissues obtained from liver cancer patients, the expression of miR-1246 was negatively correlated with CADM1 and the high expression of miR-1246 combined with low expression of CADM1 might serve as a risk factor for stage1 liver cancer patients. CONCLUSIONS: Our study showed that miR-1246, by down-regulation CADM1, enhances migration and invasion in HCC cells.

A composite of sulfur powder coated with conductive polythiophene was prepared via in situ chemical oxidative polymerization of thiophene with chloroform as the solvent and iron chloride as the oxidant. There was no chemical reaction between sulfur and polythiophene, and the composite cathode showed typical Li/S cell electrochemical reactions. The initial discharge capacity of the active materials was sulfur and the remaining capacity was sulfur after 50 cycles. The conductive polythiophene functioned in the electrode as a conducting additive and as a porous adsorbent, and effectively improved dischargeability and cyclability of the lithium/sulfur battery.

Lithium rich materials Li[Ni0.2Li0.2Mn0.6]O2 have been successfully modified by coating a thick layer of electrochemical active delithiated oxides MnOx (1.5 < x ≤ 2). The morphology observations and XRD results show that the thickness of coating layer of the modified sample 0.10MnOx·0.90Li[Ni0.2Li0.2Mn0.6]O2 is about 20 nm and there is a tiny amount of spinel structure in the coating layer. The electrochemical performance results indicate that the thick coated materials 0.10MnOx·0.90Li[Ni0.2Li0.2Mn0.6]O2 exhibit higher reversible capacity (265 mAh g−1 after 30 cycles), higher initial coulombic efficiency (90.2%), better low rate discharge capability (above 238 mAh g−1 at 1 C, 222 mAh g−1 at 2 C) and superior cycle-ability (30 cycles: 88.9%, subsequent 50 cycles after rest: 92.4%) than those of the pristine sample and conventional coated sample, respectively. The cycle voltammograms show good reversibility of the 0.10MnOx·0.90Li[Ni0.2Li0.2Mn0.6]O2 sample. The EIS tests reveal the charge transfer resistance of 0.10MnOx·0.90Li[Ni0.2Li0.2Mn0.6]O2 is lower than that of the pristine sample and conventional coated sample, respectively. Our research findings may provide significant new insights on surface modification of lithium rich cathode materials for the next generation of lithium ion batteries.

BACKGROUND: Magnetotactic bacteria have long intrigued researchers because they synthesize intracellular nano-scale (40-100 nm) magnetic particles composed of Fe3O4, termed magnetosomes. Current research focuses on the molecular mechanisms of bacterial magnetosome formation and its practical applications in biotechnology and medicine. Practical applications of magnetosomes are based on their ferrimagnetism, nanoscale size, narrow size distribution, dispersal ability, and membrane-bound structure. However, the applications of magnetosomes have not yet been developed commercially, mainly because magnetotactic bacteria are difficult to cultivate and consistent, high yields of magnetosomes have not yet been achieved. RESULTS: We report a chemostat culture technique based on pH-stat feeding that yields a high cell density of Magnetospirillum gryphiswaldense strain MSR-1 in an auto-fermentor. In a large-scale fermentor, the magnetosome yield was significantly increased by adjusting the stirring rate and airflow which regulates the level of dissolved oxygen (DO). Low concentration of sodium lactate (2.3 mmol l-1) in the culture medium resulted in more rapid cell growth and higher magnetosome yield than high concentration of lactate (20 mmol l-1). The optical density of M. gryphiswaldense cells reached 12 OD565 nm after 36 hr culture in a 42 L fermentor. Magnetosome yield and productivity were 83.23 ± 5.36 mg l-1 (dry weight) and 55.49 mg l-1 day-1, respectively, which were 1.99 and 3.32 times higher than the corresponding values in our previous study. CONCLUSIONS: Compared to previously reported methods, our culture technique with the MSR-1 strain significantly increased cell density, cell yield, and magnetosome yield in a shorter time window and thus reduced the cost of production. The cell density and magnetosome yield reported here are the highest so far achieved with a magnetotactic bacteria. Refinement of this technique will enable further increase of cell density and magnetosome yield.

Silicon monoxide, a promising silicon-based anode candidate for lithium-ion batteries, has recently attracted much attention for its high theoretical capacity, good cycle stability, low cost, and environmental benignity. Currently, the most critical challenge is to improve its low initial coulombic efficiency and significant volume changes during the charge-discharge processes. Herein, we report a binder-free monolithic electrode structure based on directly encapsulating micro-nano Si/SiOx particles into conjugated nitrogen-doped carbon frameworks to form monolithic, multi-core, cross-linking composite matrices. We utilize micro-nano Si/SiOx reduced by high-energy ball-milling SiO as active materials, and conjugated nitrogen-doped carbon formed by the pyrolysis of polyacrylonitrile both as binders and conductive agents. Owing to the high electrochemical activity of Si/SiOx and the good mechanical resiliency of conjugated nitrogen-doped carbon backbones, this specific composite structure enhances the utilization efficiency of SiO and accommodates its large volume expansion, as well as its good ionic and electronic conductivity. The annealed Si/SiOx/polyacrylonitrile composite electrode exhibits excellent electrochemical properties, including a high initial reversible capacity (2734 mA h g(-1) with 75% coulombic efficiency), stable cycle performance (988 mA h g(-1) after 100 cycles), and good rate capability (800 mA h g(-1) at 1 A g(-1) rate). Because the composite is naturally abundant and shows such excellent electrochemical performance, it is a promising anode candidate material for lithium-ion batteries. The binder-free monolithic architectural design also provides an effective way to prepare other monolithic electrode materials for advanced lithium-ion batteries.

Metastasis is one of the hallmarks of cancer malignancy that usually causes more detrimental effects than a primary tumor. Many microRNAs were reported to be involved in the process of tumor metastasis. Hep11 and Hep12 cells were derived from primary and recurrence (intrahepatic metastatic) sites of hepatocellular carcinoma (HCC), respectively. Hep12 exhibited a higher invasive and migratory potential than Hep11. There was also a significantly higher expression of miR-9 in Hep12 cells than in Hep11 cells. Further studies in HCC cell lines demonstrated that miR-9 could promote tumor cell migration and invasion. In addition, miR-9 downregulated KLF17 protein expression by targeting the 3'UTR region of the KLF17 gene directly. As a transcription factor, KLF17 directly acted on the promoters of EMT-related genes (ZO-1, Vimentin and Fibronectin (FN)) in HCC cell lines. Therefore, we conclude that miR-9 may possibly promote HCC migration and invasion through regulation of KLF17.