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Find video protocols related to scientific articles indexed in Pubmed.
Electronic bandgap and edge reconstruction in phosphorene materials.
Nano Lett.
PUBLISHED: 10-30-2014
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Single-layer black phosphorus (BP), or phosphorene, is a highly anisotropic two-dimensional elemental material possessing promising semiconductor properties for flexible electronics. However, the direct bandgap of single-layer black phosphorus predicted theoretically has not been directly measured, and the properties of its edges have not been considered in detail. Here we report atomic scale electronic variation related to strain-induced anisotropic deformation of the puckered honeycomb structure of freshly cleaved black phosphorus using a high-resolution scanning tunneling spectroscopy (STS) survey along the light (x) and heavy (y) effective mass directions. Through a combination of STS measurements and first-principles calculations, a model for edge reconstruction is also determined. The reconstruction is shown to self-passivate most dangling bonds by switching the coordination number of phosphorus from 3 to 5 or 3 to 4.
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Endoplasmic Reticulum Stress-Mediated Apoptotic Pathway Is Involved in Corpus Luteum Regression in Rats.
Reprod Sci
PUBLISHED: 10-22-2014
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Endoplasmic reticulum stress (ERS), which is a novel pathway of regulating cellular apoptosis and the function of ERS during corpus luteum (CL) regression, is explored. Early-luteal stage (day 2), mid-luteal stage (day 7), and late-luteal stage (day 14 and 20) were induced, and the apoptosis of luteal cells was detected by a terminal 2'-deoxyuridine 5'-triphosphate nick-end labeling (TUNEL) assay. The apoptotic cells were increased with the regression of CL, especially during the late-luteal stage. The ERS markers glucose-regulated protein 78 (Grp78), CCAAT/enhancer-binding protein homologous protein (CHOP), X-box binding protein 1 (XBP1), activating transcription factor 6? (ATF6?), eukaryotic initiation factor 2? (eIF2?), inositol-requiring protein 1? (IRE1?), caspase 12, and apoptosis marker caspase 3 were analyzed by real-time polymerase chain reaction (PCR) and immunohistochemistry, in agreement with the results of the TUNEL assay; the expression levels of CHOP, caspase 12, and caspase 3 were increased during the process of CL regression. Luteal cells were isolated and cultured in vitro, and the apoptosis of luteal cells was induced by prostaglandin F2?. The ERS was attenuated by the ERS inhibitor tauroursodeoxycholic acid, and the apoptotic rate was analyzed by flow cytometry. The ERS markers Grp78, CHOP, XBP1s, ATF6?, eIF2?, IRE1?, caspase 12, and apoptotic execute marker caspase 3 were analyzed by real-time PCR and immunofluorescence, and the results suggested that the expression of CHOP, caspase 12, and caspase 3 were increased, and there was increased apoptosis of luteal cells. But the expression of IRE1?/XBP1s and eIF2? was not detected. Taken together, the ERS is involved in the CL regression of rats through the CHOP and caspase 12 pathway.
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All-optical switching with 1-ps response time in a DDMEBT enabled silicon grating coupler/resonator hybrid device.
Opt Express
PUBLISHED: 10-17-2014
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An amorphous film of the third-order nonlinear optical material DDMEBT was spun onto silicon chips for the first time, filling 80 nm lithographic features. A 710 ?m2 device was designed, fabricated, and tested that acts both as a nonlinear resonator switch and as an input/output grating coupler to a perfectly vertical single mode fiber. Autocorrelation and spectral measurements indicate the device has <1 ps response time, 4 nm of switching bandwidth, and 4 dB of on/off contrast. With sufficient power, this all-optical device can potentially modulate a single optical carrier frequency in excess of 1 THz.
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[Clinicopathological and CT features of mucinous cystic neoplasms of the pancreas].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 09-23-2014
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To evaluate the clinicopathological and CT features of mucinous cystic neoplasms (MCNs) of the pancreas and analyze the correlative risk factors for malignant pancreatic mucinous cystic neoplasms.
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Successful Transient Expression of Cas9 and Single Guide RNA Genes in Chlamydomonas reinhardtii.
Eukaryotic Cell
PUBLISHED: 09-19-2014
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The clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system has become a powerful and precise tool for targeted gene modification (e.g., gene knockout and gene replacement) in numerous eukaryotic organisms. Initial attempts to apply this technology to a model, the single-cell alga, Chlamydomonas reinhardtii, failed to yield cells containing edited genes. To determine if the Cas9 and single guide RNA (sgRNA) genes were functional in C. reinhardtii, we tested the ability of a codon-optimized Cas9 gene along with one of four different sgRNAs to cause targeted gene disruption during a 24-h period immediately following transformation. All three exogenously supplied gene targets as well as the endogenous FKB12 (rapamycin sensitivity) gene of C. reinhardtii displayed distinct Cas9/sgRNA-mediated target site modifications as determined by DNA sequencing of cloned PCR amplicons of the target site region. Success in transient expression of Cas9 and sgRNA genes contrasted with the recovery of only a single rapamycin-resistant colony bearing an appropriately modified FKB12 target site in 16 independent transformation experiments involving >10(9) cells. Failure to recover transformants with intact or expressed Cas9 genes following transformation with the Cas9 gene alone (or even with a gene encoding a Cas9 lacking nuclease activity) provided strong suggestive evidence for Cas9 toxicity when Cas9 is produced constitutively in C. reinhardtii. The present results provide compelling evidence that Cas9 and sgRNA genes function properly in C. reinhardtii to cause targeted gene modifications and point to the need for a focus on development of methods to properly stem Cas9 production and/or activity following gene editing.
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Tree growth and intrinsic water-use efficiency of inland riparian forests in northwestern China: evaluation via ?13C and ?18O analysis of tree rings.
Tree Physiol.
PUBLISHED: 08-21-2014
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The rising atmospheric CO2 concentration (Ca) has increased tree growth and intrinsic water-use efficiency (iWUE). However, the magnitude of this effect on long-term iWUE and whether this increase could stimulate the growth of riparian forests in extremely arid regions remain poorly understood. We investigated the relationship between growth [ring width; basal area increment (BAI)] and iWUE in a riparian Populus euphratica Oliv. forest to test whether growth was enhanced by increasing CO2 and whether this compensated for environmental stresses in the lower reaches of the inland Heihe River, northwestern China. We accomplished this using dendrochronological methods and carbon (?(13)C) and oxygen (?(18)O) isotopic analysis. We found an increase in BAI before 1958, followed by a decrease from 1958 to 1977 and an increase to a peak around 2000. Tree-ring carbon discrimination (?) and ?(18)O indicated significant negative overall trends from 1920 to 2012. However, the relationship shifted in strength and direction around 1977 from significantly negative to a weak connection. The seasonal minimum temperature in April to July showed strong influence on ?, and ?(18)O was controlled by relative humidity (negatively correlated) and temperature (positively correlated) in June and July. The patterns of internal to atmospheric CO2 (Ci/Ca) suggest a specific adaptation of tree physiology to increasing CO2. Intrinsic water-use efficiency increased significantly (by 36.4%) during the study period. The increased iWUE explained 19.8 and 39.1% of the observed yearly and high-frequency (first-order difference) variations in BAI, respectively, after 1977. Our results suggest significant CO2 stimulation of riparian tree growth, which compensated for the negative influences of reductions in river streamflow and a drying climate during the study period.
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Phylogeography of the finless porpoise (genus Neophocaena): testing the stepwise divergence hypothesis in the northwestern Pacific.
Sci Rep
PUBLISHED: 08-19-2014
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We used 344 mitochondrial control region (717?bp) sequences from the finless porpoise (genus Neophocaena) from the northwestern Pacific to investigate the extent and manner in which past climatic oscillations may have shaped patterns of genetic diversity for this marine mammal. Both SplitsTree and Analysis of Molecular Variance (AMOVA) revealed the presence of a deep divergence among N. phocaenoides in subtropical waters compared with N. asiaeorientalis in temperate waters. Results from Migrate-n indicated that migration increased along the continent during the early Pleistocene period. Migration increased, although to a lesser extent than that during the Pleistocene, along the marginal shelf in the Yellow/Bohai Sea during the Last Glacial Maximum (LGM) due to a shortening coastline. Our results suggest that the current patterns of genetic diversity of Neophocaena vary at a hierarchy on a temporal and spatial scale, and phylogeographic history should be taken into account when examining species population structure and taxonomy.
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A method to evaluate genome-wide methylation in archival formalin-fixed, paraffin-embedded ovarian epithelial cells.
PLoS ONE
PUBLISHED: 08-18-2014
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The use of DNA from archival formalin and paraffin embedded (FFPE) tissue for genetic and epigenetic analyses may be problematic, since the DNA is often degraded and only limited amounts may be available. Thus, it is currently not known whether genome-wide methylation can be reliably assessed in DNA from archival FFPE tissue.
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[Effectiveness study on minimally invasive transforaminal lumbar interbody fusion assisted with microscope in treatment of lumbar spondylolisthesis].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 07-31-2014
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To investigate the effectiveness of minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) assisted with microscope in treatment of lumbar spondylolisthesis.
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Quantitative study of protein-protein interactions by quartz nanopipettes.
Nanoscale
PUBLISHED: 07-25-2014
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In this report, protein-modified quartz nanopipettes were used to quantitatively study protein-protein interactions in attoliter sensing volumes. As shown by numerical simulations, the ionic current through the conical-shaped nanopipette is very sensitive to the surface charge variation near the pore mouth. With the appropriate modification of negatively charged human neuroglobin (hNgb) onto the inner surface of a nanopipette, we were able to detect concentration-dependent current change when the hNgb-modified nanopipette tip was exposed to positively charged cytochrome c (Cyt c) with a series of concentrations in the bath solution. Such current change is due to the adsorption of Cyt c to the inner surface of the nanopipette through specific interactions with hNgb. In contrast, a smaller current change with weak concentration dependence was observed when Cyt c was replaced with lysozyme, which does not specifically bind to hNgb. The equilibrium dissociation constant (KD) for the Cyt c-hNgb complex formation was derived and the value matched very well with the result from surface plasmon resonance measurement. This is the first quantitative study of protein-protein interactions by a conical-shaped nanopore based on charge sensing. Our results demonstrate that nanopipettes can potentially be used as a label-free analytical tool to quantitatively characterize protein-protein interactions.
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A rapid live-cell ELISA for characterizing antibodies against cell surface antigens of Chlamydomonas reinhardtii and its use in isolating algae from natural environments with related cell wall components.
BMC Plant Biol.
PUBLISHED: 07-18-2014
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BackgroundCell walls are essential for most bacteria, archaea, fungi, algae and land plants to provide shape, structural integrity and protection from numerous biotic and abiotic environmental factors. In the case of eukaryotic algae, relatively little is known of the composition, structure or mechanisms of assembly of cell walls in individual species or between species and how these differences enable algae to inhabit a great diversity of environments. In this paper we describe the use of camelid antibody fragments (VHHs) and a streamlined ELISA assay as powerful new tools for obtaining mono-specific reagents for detecting individual algal cell wall components and for isolating algae that share a particular cell surface component.ResultsTo develop new microalgal bioprospecting tools to aid in the search of environmental samples for algae that share similar cell wall and cell surface components, we have produced single-chain camelid antibodies raised against cell surface components of the single-cell alga, Chlamydomonas reinhardtii. We have cloned the variable-region domains (VHHs) from the camelid heavy-chain-only antibodies and overproduced tagged versions of these monoclonal-like antibodies in E. coli. Using these VHHs, we have developed an accurate, facile, low cost ELISA that uses live cells as a source of antigens in their native conformation and that requires less than 90 minutes to perform. This ELISA technique was demonstrated to be as accurate as standard ELISAs that employ proteins from cell lysates and that generally require >24 hours to complete. Among the cloned VHHs, VHH B11, exhibited the highest affinity (EC50¿<¿1nM) for the C. reinhardtii cell surface. The live-cell ELISA procedure was employed to detect algae sharing cell surface components with C. reinhardtii in water samples from natural environments. In addition, mCherry-tagged VHH B11 was used along with fluorescence activated cell sorting (FACS) to select individual axenic isolates of presumed wild relatives of C. reinhardtii and other Chlorphyceae from the same environmental samples.ConclusionsCamelid antibody VHH domains provide a highly specific tool for detection of individual cell wall components of algae and for allowing the selection of algae that share a particular cell surface molecule from diverse ecosystems.
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Contribution of homeostatic chemokines CCL19 and CCL21 and their receptor CCR7 to coronary artery disease.
Arterioscler. Thromb. Vasc. Biol.
PUBLISHED: 07-02-2014
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Our aim was to identify the role of the homeostatic chemokines CCL19 and CCL21 and their common receptor CCR7 in atherogenesis and to study the relationships between CCL19, CCL21, and CCR7 gene variants and coronary artery disease in a Chinese Han population.
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Polarized photocurrent response in black phosphorus field-effect transistors.
Nanoscale
PUBLISHED: 06-27-2014
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We investigate electrical transport and optoelectronic properties of field effect transistors (FETs) made from few-layer black phosphorus (BP) crystals down to a few nanometers. In particular, we explore the anisotropic nature and photocurrent generation mechanisms in BP FETs through spatial-, polarization-, gate-, and bias-dependent photocurrent measurements. Our results reveal that the photocurrent signals at BP-electrode junctions are mainly attributed to the photovoltaic effect in the off-state and photothermoelectric effect in the on-state, and their anisotropic feature primarily results from the directional-dependent absorption of BP crystals.
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Chemically induced Jahn-Teller ordering on manganite surfaces.
Nat Commun
PUBLISHED: 06-26-2014
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Physical and electrochemical phenomena at the surfaces of transition metal oxides and their coupling to local functionality remains one of the enigmas of condensed matter physics. Understanding the emergent physical phenomena at surfaces requires the capability to probe the local composition, map order parameter fields and establish their coupling to electronic properties. Here we demonstrate that measuring the sub-30-pm displacements of atoms from high-symmetry positions in the atomically resolved scanning tunnelling microscopy allows the physical order parameter fields to be visualized in real space on the single-atom level. Here, this local crystallographic analysis is applied to the in-situ-grown manganite surfaces. In particular, using direct bond-angle mapping we report direct observation of structural domains on manganite surfaces, and trace their origin to surface-chemistry-induced stabilization of ordered Jahn-Teller displacements. Density functional calculations provide insight into the intriguing interplay between the various degrees of freedom now resolved on the atomic level.
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Employment is maintained and sick days decreased in psoriasis/psoriatic arthritis patients with etanercept treatment.
BMC Dermatol.
PUBLISHED: 06-04-2014
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Psoriasis and psoriatic arthritis (PsA) impair quality of life, including reduction in employment or job duties. The PRESTA (Psoriasis Randomized Etanercept STudy in Patients with Psoriatic Arthritis) study, a randomized, double-blind, two-dose trial, examined the efficacy of etanercept treatment in patients with moderate-to-severe plaque psoriasis and PsA and the main results have been presented previously. This analysis examined employment status, job duties and sick days, pre-defined endpoints in PRESTA, among this patient population.
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[Allogeneic bone transplantation for pelvic reconstruction of large skeletal defects after tumor resection].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-22-2014
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To investigate the short-term effectiveness of allogeneic bone transplantation for pelvic reconstruction of large skeletal defects after tumor resection.
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[Application of contrast-enhanced ultrasound in needle biopsy of tuberculous cervical lymph node].
Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 05-14-2014
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To study the value of contrast-enhanced ultrasound in tuberculous cervical lymph node biopsy.
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Facility for low-temperature spin-polarized-scanning tunneling microscopy studies of magnetic/spintronic materials prepared in situ by nitride molecular beam epitaxy.
Rev Sci Instrum
PUBLISHED: 05-03-2014
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Based on the interest in, as well as exciting outlook for, nitride semiconductor based structures with regard to electronic, optoelectronic, and spintronic applications, it is compelling to investigate these systems using the powerful technique of spin-polarized scanning tunneling microscopy (STM), a technique capable of achieving magnetic resolution down to the atomic scale. However, the delicate surfaces of these materials are easily corrupted by in-air transfers, making it unfeasible to study them in stand-alone ultra-high vacuum STM facilities. Therefore, we have carried out the development of a hybrid system including a nitrogen plasma assisted molecular beam epitaxy/pulsed laser epitaxy facility for sample growth combined with a low-temperature, spin-polarized scanning tunneling microscope system. The custom-designed molecular beam epitaxy growth system supports up to eight sources, including up to seven effusion cells plus a radio frequency nitrogen plasma source, for epitaxially growing a variety of materials, such as nitride semiconductors, magnetic materials, and their hetero-structures, and also incorporating in situ reflection high energy electron diffraction. The growth system also enables integration of pulsed laser epitaxy. The STM unit has a modular design, consisting of an upper body and a lower body. The upper body contains the coarse approach mechanism and the scanner unit, while the lower body accepts molecular beam epitaxy grown samples using compression springs and sample skis. The design of the system employs two stages of vibration isolation as well as a layer of acoustic noise isolation in order to reduce noise during STM measurements. This isolation allows the system to effectively acquire STM data in a typical lab space, which during its construction had no special and highly costly elements included, (such as isolated slabs) which would lower the environmental noise. The design further enables tip exchange and tip coating without breaking vacuum, and convenient visual access to the sample and tip inside a superconducting magnet cryostat. A sample/tip handling system is optimized for both the molecular beam epitaxy growth system and the scanning tunneling microscope system. The sample/tip handing system enables in situ STM studies on epitaxially grown samples, and tip exchange in the superconducting magnet cryostat. The hybrid molecular beam epitaxy and low temperature scanning tunneling microscopy system is capable of growing semiconductor-based hetero-structures with controlled accuracy down to a single atomic-layer and imaging them down to atomic resolution.
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Early clinical experience with a novel self-expanding percutaneous stent-valve in the native right ventricular outflow tract.
Catheter Cardiovasc Interv
PUBLISHED: 03-31-2014
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Balloon expandable transcatheter pulmonary valve systems are not applicable to the large majority of patients with chronic severe pulmonary regurgitation (PR) following surgical right ventricular outflow tract (RVOT) rehabilitation. This report describes the clinical use and short-term follow-up of a novel transcatheter self-expanding pulmonary valve system (Venus P Valve) for rehabilitation of the RVOT in patients with chronic severe PR.
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Accurate inference of local phased ancestry of modern admixed populations.
Sci Rep
PUBLISHED: 03-25-2014
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Population stratification is a growing concern in genetic-association studies. Averaged ancestry at the genome level (global ancestry) is insufficient for detecting the population substructures and correcting population stratifications in association studies. Local and phase stratification are needed for human genetic studies, but current technologies cannot be applied on the entire genome data due to various technical caveats. Here we developed a novel approach (aMAP, ancestry of Modern Admixed Populations) for inferring local phased ancestry. It took about 3 seconds on a desktop computer to finish a local ancestry analysis for each human genome with 1.4-million SNPs. This method also exhibits the scalability to larger datasets with respect to the number of SNPs, the number of samples, and the size of reference panels. It can detect the lack of the proxy of reference panels. The accuracy was 99.4%. The aMAP software has a capacity for analyzing 6-way admixed individuals. As the biomedical community continues to expand its efforts to increase the representation of diverse populations, and as the number of large whole-genome sequence datasets continues to grow rapidly, there is an increasing demand on rapid and accurate local ancestry analysis in genetics, pharmacogenomics, population genetics, and clinical diagnosis.
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The development of WEEE management and effects of the fund policy for subsidizing WEEE treating in China.
Waste Manag
PUBLISHED: 03-14-2014
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The consumption of electrical and electronic equipment is surging, so is the generation of waste electrical and electronic equipment (WEEE). Due to the large quantity, high potential risk and valuable capacity of WEEE, many countries are taking measures to regulate the management of WEEE. The environmental pollution and human health-harming problems caused by irregular treatment of WEEE in China make the government pay more and more attention to its management. This paper reviews the development of WEEE management in China, introduces the new policy which is established for WEEE recycling and especially analyzes the effectiveness of the policy, including huge recovery, formation of new recycling system, strict supervision to related enterprises, and the stimulation to public awareness. Based on the current achievement, some recommendations are given to optimize the WEEE management in China.
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The preliminary evaluation on cholesterol-modified pullulan as a drug nanocarrier.
Drug Deliv
PUBLISHED: 03-13-2014
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Abstract To further develop cholesterol-modified pullulan self-aggregated nanoparticles (CHSPNs) as a drug nanocarrier, CHSP was synthesized and characterized. Its cholesterol degree determined by (1)H NMR was 5.2 cholesterol groups per hundred glucose units. CHSPNs were prepared in aqueous media and characterized by dynamic laser light-scattering (DLS), zeta potential and transmission electron microscopy (TEM). These nanoparticles were almost spherical in shape, and the zeta potentials of CHSPNs were near zero in aqueous media. CHSPNs can be stable at least 2 months with no significant size and zeta potential changes. Single dose toxicity test in mice was investigated for the safety evaluation of CHSPNs as a drug nanocarrier, and the result showed CHSPNs were well tolerated at the dose of 200?mg/kg in mice. Epirubicin (EPI)-loaded CHSPNs (EPI-CHSPNs) were prepared and the in vivo pharmacokinetics and biodistribution were studied. Compared with the EPI solution, EPI-CHSPNs have exhibited higher plasma drug concentration, longer half-life time (t1/2) and the larger area under-the-curve (AUC). Moreover, the drug level of EPI-CHSPNs increased in liver and decreased in heart. The results indicated that CHSPNs were stable, safe and may be a promising drug delivery carrier.
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In situ transmission electron microscopy observation of electrochemical sodiation of individual Co?S?-filled carbon nanotubes.
ACS Nano
PUBLISHED: 03-12-2014
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The comprehension of fundamental electrochemical behavior and sodiation mechanism is critical for the design of high-performance electrode materials for sodium-ion (Na-ion) batteries. In this paper, the electrochemical sodiation process and microstructure evolution of individual Co9S8-filled carbon nanotubes (CNTs) have been directly visualized and studied using in situ transmission electron microscopy. Upon the first sodiation, a reaction front propagates progressively along the filling nanowire, causing the filled CNT to inflate. The filled CNTs behave differently depending on their structures and the magnitude of the sodiation voltage. For a Co9S8-filled CNT with an open end, the sodiated Co9S8 filler shows a substantial axial elongation of 120.8% and a small radial swelling due to the extrusion of CNT walls. In contrast, the closed CNT shows a major radial expansion of 40.6% and a small axial elongation because of the mechanical confinement of the carbon shells. After sodiation, the spacing between the carbon shells increases from 3.4 to 3.8 Å due to the Na(+)-ion insertion and the single-crystalline Co9S8 filler converts to numerous Co nanograins dispersed in a Na2S matrix. Compared with the gentle microstructure evolution of the CNT under small charging voltage, a strong electrochemical reaction accompanying drastic swelling and fracturing of CNT shells is observed for the CNT electrode under large charging voltage. Our observations provide direct evidence and important insights for the electrochemical process of CNT-based composite materials in Na-ion batteries.
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Prognostic factors for survival of patients with ampullary carcinoma after local resection.
ANZ J Surg
PUBLISHED: 03-03-2014
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Local resection (LR) is a potentially effective alternative to pancreaticoduodenectomy for treatment of ampullary cancer, but the prognostic factors remain undefined. The purpose of this study was to identify the prognostic factors for ampullary cancer patients who had undergone LR.
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DNA methylation of pituitary growth hormone is involved in male growth superiority of Nile tilapia (Oreochromis niloticus).
Comp. Biochem. Physiol. B, Biochem. Mol. Biol.
PUBLISHED: 03-02-2014
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Growth hormone (GH) and its receptors are critical regulators of somatic growth and metabolism. It has been shown in mammals that the methylation of cytosines within the GH promoter plays a key role in regulating transcripts expression. In the present study, the GH, GHR1 and GHR2 proximal promoters were identified and the methylation levels of these genes in corresponding tissues were assayed. The results suggested that significant arising of GH putative promoter methylation levels in pituitary was observed in females compared with males. However, no such sex-specific changes were found in GHR1 and GHR2 promoters. The GH mRNA expression also was influenced by GH promoter methylation levels in pituitary, which resulted in the higher growth rate of Nile tilapia males. Meanwhile, the methylation levels of GH putative promoter were negatively correlated with growth rate as well as mRNA expression of GH. Furthermore, the methylation of specific E-Box CpG site is also negatively related to the mRNA expression of GH in pituitary. Taken together, our data provide an epigenetic mechanism of explicating the sex duality in phenotypic plasticity of growth rate in male and female of Nile tilapia.
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Bond competition and phase evolution on the IrTe2 surface.
Nat Commun
PUBLISHED: 02-26-2014
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Compounds with incommensurate structural modulations have been extensively studied in last several decades. However, the relationship between structurally incommensurate/commensurate phases and associated electronic states remains enigmatic. Here we report the coexisting of complex incommensurate structures and highly unusual electronic roughness on the surface of in situ cleaved IrTe2 by using scanning tunnelling microscopy/spectroscopy, corroborated with extensive density-functional theory calculations. This behaviour is traced to structural instability, which induces a structural transition from a trigonal to a triclinic lattice below transition temperature, giving rise to the formation of unidirectional structural modulations with distinct wavelengths, accompanied by the opening of a 'pseudo'-gap in the surface layer. With further cooling the surface adopts a structure that reflects an ~6 × periodicity that is different from the bulk 5 × periodicity. Calculations show that the structure distortion is not associated with a charge density wave, but is rather associated with Te p-electron bonding.
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Generation, collection and transportation, disposal and recycling of kitchen waste: a case study in Shanghai.
Waste Manag Res
PUBLISHED: 02-12-2014
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With respect to waste sorting, Shanghai sets an example for other Chinese cities on the standardized treatment of kitchen waste (KW) in China. According to the results of investigation, about 560 kilo tons of KW from different sources in Shanghai were produced in 2011. Of this, 45.6% (255.6 kilo tons) was collected and transported properly by a comprehensive and formal collection and transportation system. Landfilling and incineration, which are the traditional treatment technologies used, show downward trends because of increasing environmental awareness and land restrictions. Feed production, composting and biodiesel refining play increasingly important roles in the recycling of KW. Safe disposal, reduced KW quantity, public education, and technological innovation are still problematic issues and need to be considered in future waste management in Shanghai.
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The diagnostic value of tumor biomarkers for detecting hepatocellular carcinoma accompanied by portal vein tumor thrombosis.
Cell Biochem. Biophys.
PUBLISHED: 02-07-2014
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Tumor biomarkers commonly used for the detection of hepatocellular carcinoma (HCC) complicated with portal vein tumor thrombosis (PVTT) do not show satisfactory sensitivity and specificity. This study assesses the diagnostic value of the tumor biomarkers for the diagnosis of HCC with PVTT. A retrospective study was conducted on 475 patients diagnosed as HCC with PVTT and 977 patients diagnosed with HCC by imaging and requiring surgery at our hospital from January 1993 to January 2011. Serum alpha-fetoprotein AFP, carcinoembryonic antigen, and cancer antigen 125 (Ca125) of the patients were studied. No significant differences were observed in the patients' general characteristics. The receiver operating characteristic (ROC) analysis showed that the cut-off of AFP and Ca125 was 32.91 ng/ml and 113.65 U/ml, respectively (AUC = 0.814 and 0.783). The parallel testing with AFP and Ca125 has a sensitivity of 0.909 and a specificity of 0.410; the serial testing has a sensitivity of 0.520 and a specificity of 0.97. The condition of AFP ? 20,000 ng/ml can detect HCC with PVTT with a sensitivity of 0.24, a specificity of 0.96, and an accuracy of 0.73 and positive screening of 0.76. The standard of both AFP > 32.91 ng/ml and Ca125 > 113.65 U/ml or AFP ? 20,000 ng/ml can detect HCC with PVTT with a specificity of 0.97 and 0.96, respectively, providing important guidance for clinical practice.
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Hydrothermal decomposition of liquid crystal in subcritical water.
J. Hazard. Mater.
PUBLISHED: 02-02-2014
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Treatment of liquid crystal has important significance for the environment protection and human health. This study proposed a hydrothermal process to decompose the liquid crystal of 4-octoxy-4'-cyanobiphenyl. Experiments were conducted with a 5.7 mL stainless tube reactor and heated by a salt-bath. Factors affecting the decomposition rate of 4-octoxy-4'-cyanobiphenyl were evaluated with HPLC. The decomposed liquid products were characterized by GC-MS. Under optimized conditions i.e., 0.2 mL H2O2 supply, pH value 6, temperature 275°C and reaction time 5 min, 97.6% of 4-octoxy-4'-cyanobiphenyl was decomposed into simple and environment-friendly products. Based on the mechanism analysis and products characterization, a possible hydrothermal decomposition pathway was proposed. The results indicate that hydrothermal technology is a promising choice for liquid crystal treatment.
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Expression and localization of SerpinB11 in mouse uteri during peri-implantation and the estrous cycle.
Cell Tissue Res.
PUBLISHED: 01-29-2014
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Serine protease inhibitor (Serpin) B11 has been identified as a novel serine protease inhibitor but the biological functions of SerpinB11 in female reproduction are unknown. Therefore, we investigate the spatiotemporal expression and regulation of SerpinB11 during the peri-implantation period. SerpinB11 mRNA and protein were detected in the uteri of pregnant mice on days 1-8 (day 1?=?presence of a vaginal plug). SerpinB11 protein was localized in the embryonic implantation site on day 5 when embryo implantation occurred and was also strongly expressed in the primary decidual zone on day 6 and secondary decidual zone on days 7 and 8. The expression of SerpinB11 was induced by the activated blastocyst (based on patterns of expression during pseudopregnancy and delayed implantation) and by artificially induced decidualization. Moreover, expression of SerpinB11 was regulated by estradiol and progesterone in ovariectomized mice. The results were further supported by data from the estrous cycle. Thus, SerpinB11 is probably involved in embryo implantation and decidualization.
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Hypertension detection, management, control and associated factors among residents accessing community health services in Beijing.
Sci Rep
PUBLISHED: 01-28-2014
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The aim of this study was to analyse high blood pressure detection, management, control and associated factors among residents accessing community health services (CHSs) in Beijing. We screened for HBP in 9524 individuals aged 50 years or older who accessed care in four Beijing CHSs. Among the 9397 residents with questionnaire responses that qualified them for inclusion in the study, 5029 patients with HBP were identified, 1510 (i.e., 30% of the HBP patient group) of whom were newly identified cases. The rate of hypertension detection was 53.5%. Among the 5029 HBP patients, the rates of awareness, treatment and control of hypertension were 70.0%, 62.1% and 29.6%, respectively. In general, the rate of hypertension control was higher when the rates of hypertension awareness and treatment were higher in subgroups stratified by different sociodemographic and risk factors, except for the overweight and obesity subgroups. In conclusion, suboptimal HBP awareness, treatment, and control are still major problems confronting CHSs in Beijing. Control of hypertension in the population may be improved by increasing awareness and improving the treatment of hypertension in CHSs.
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Hepatic perivascular epithelioid cell tumors-not otherwise specified: a case report.
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 01-28-2014
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Neoplasms of perivascular epithelioid cells (PEComas) are characterized by epithelioid to spindle cells with eosinophilic to clear cytoplasm, an intimate relationship with blood vessels, and coexpression of myoid and melanocytic immunohistochemical markers. While most reported hepatic PEComas, such as angiomyolipoma (AML), behave in a benign fashion, emerging PEComas cases without typical characteristics require further clarification. We report a case of primary hepatic perivascular epithelioid cell tumors-not otherwise specified (HPEComas-NOS) with untypical pathological and immunohistochemical features compared to those of the benign hepatic AML cases. HPEComas-NOS may represent a special type of PEComas classified as having "malignant potential" or at "high risk of aggressive behavior", suggesting the need for further clarification of hepatic PEComas and long-term follow-up of patients with HPEComas-NOS.
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Neuroprotective effects of therapeutic hypercapnia on spatial memory and sensorimotor impairment via anti-apoptotic mechanisms after focal cerebral ischemia/reperfusion.
Neurosci. Lett.
PUBLISHED: 01-23-2014
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A number of studies have demonstrated that therapeutic hypercapnia ameliorates neurological deficits and attenuates the histological damage of cerebral ischemia-reperfusion injury. However, the effects of therapeutic hypercapnia on impaired spatial memory have not been reported. Here we aimed to investigate the effects and mechanisms of therapeutic hypercapnia on spatial memory in a rat model of focal cerebral ischemia induced by middle cerebral artery occlusion/reperfusion (MCAO/R). Adult male rats were randomly assigned into three experimental groups: sham (sham operation), IR (MCAO/R), and hypercapnia [arterial blood CO2 tension (PaCO2) 80-100 mmHg+IR] groups. Sensorimotor deficits and spatial memory testing were evaluated by an 18-point scoring system and an 8-arm radial maze task, respectively. The hippocampal histological damage and the percentage of apoptotic neurons were evaluated by hematoxylin and eosin (HE) staining as well as flow cytometry. Western blotting was used to investigate the changes of the apoptosis-related Bcl-2 and Bax proteins. The results indicated that hypercapnia treatment significantly improved the abilities of impaired sensorimotor and spatial memory after MCAO/R. Moreover, hypercapnia treatment significantly increased the percentage of surviving neurons and decreased the percentage of apoptotic neurons in the hippocampus after MCAO/R damage. The expressions of anti-apoptotic protein Bcl-2 and pro-apoptotic protein Bax were significantly increased and decreased in the hypercapnia treated rats, respectively. These findings suggest that therapeutic hypercapnia can attenuate neuronal apoptosis and improve impaired spatial memory and sensorimotor after MCAO/R, which may be attributable to its anti-apoptotic effects through modulation of apoptosis-related protein.
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Global and regional burden of stroke during 1990-2010: findings from the Global Burden of Disease Study 2010.
Lancet
PUBLISHED: 01-23-2014
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Although stroke is the second leading cause of death worldwide, no comprehensive and comparable assessment of incidence, prevalence, mortality, disability, and epidemiological trends has been estimated for most regions. We used data from the Global Burden of Diseases, Injuries, and Risk Factors Study 2010 (GBD 2010) to estimate the global and regional burden of stroke during 1990-2010.
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A bovine viral diarrhea virus type 1a strain in China: isolation, identification, and experimental infection in calves.
Virol. J.
PUBLISHED: 01-17-2014
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Bovine viral diarrhea virus (BVDV) is one of the most important pathogens in cattle. Previously, BVDV sub-genotypes of 1b, 1c, 1d, and 1 m were detected in China. However, isolation of BVDV type 1a from cattle has not been reported in China. In 2010, twenty nasal swabs and blood samples were collected from the cattle suspected BVDV infection in Henan province, China. A BVDV isolate was isolated using cell culture, and the pathogenesis of the virus isolate was studied.
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Human herpes virus 8-unrelated primary effusion lymphoma-like lymphoma diagnosed by fluorodeoxyglucose positron emission tomography/computer tomography and laparoscopy.
Oncol Lett
PUBLISHED: 01-08-2014
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Human herpes virus 8-unrelated primary effusion lymphoma (PEL)-like lymphoma is a rare type of large B cell lymphoma. This report presents the case of a male with abdominal pain and distension who was found to have massive ascites and enhanced peritoneum, mesenterium and greater omentum on enhanced computer tomography (CT) scan with negative ascitic cytology. The diagnosis of PEL-like lymphoma was established by fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT and laparoscopic biopsy of the greater omentum. To the best of our knowledge, this is only the second case report to describe FDG PET/CT presentations of PEL-like lymphoma, and the first case report to use laparoscopy for diagnosis.
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The impacts of thyroid function on the diagnostic accuracy of cystatin C to detect acute kidney injury in ICU patients: a prospective, observational study.
Crit Care
PUBLISHED: 01-03-2014
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Cystatin C (Cysc) could be affected by thyroid function both in vivo and in vitro and thereby may have limited ability to reflect renal function. We aimed to assess the association between Cysc and thyroid hormones as well as the effect of thyroid function on the diagnostic accuracy of Cysc to detect acute kidney injury (AKI).
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Effects of post-discharge nurse-led telephone supportive care for patients with chronic kidney disease undergoing peritoneal dialysis in China: a randomized controlled trial.
Perit Dial Int
PUBLISHED: 01-02-2014
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Patients with end-stage renal failure (ESRF) need integrated health care to maintain a desirable quality of life. Studies suggest that post-discharge nurseled telephone support has a positive effect for patients suffering from chronic diseases. But the post-discharge care is under-developed in mainland China and the effects of post-discharge care on patients with peritoneal dialysis have not been conclusive.
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Evaluation of the diagnostic performance of magnetic resonance spectroscopy in brain tumors: a systematic review and meta-analysis.
PLoS ONE
PUBLISHED: 01-01-2014
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The aim of this study was to determine the suitability of magnetic resonance spectroscopy (MRS) for screening brain tumors, based on a systematic review and meta-analysis of published data on the diagnostic performance of MRS.
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ICU-Onset Clostridium difficile Infection in a University Hospital in China: A Prospective Cohort Study.
PLoS ONE
PUBLISHED: 01-01-2014
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A prospective study was conducted to investigate the incidence, clinical profiles and outcome of ICU-onset CDI in a 50-bed medical ICU at a university hospital in China. Stools were collected from patients who developed ICU-onset diarrhea and was screened for tcdA (toxin A gene) and tcdB (toxin B gene) by PCR. CDI cases were compared with the ICU-onset non-CDI diarrhea cases for demographics, comorbidities, potential risk factors, major laboratory findings and outcomes. Stool samples from CDI cases were subjected to C. difficile culture and C. difficile isolates were screened for tcdA, tcdB and the binary toxin genes (cdtA and cdtB) using multiplex PCR. Strain typing of toxigenic C. difficile isolates was performed using multilocus sequence typing. There were 1,277 patients in the ICU during the study period and 124 (9.7%) developed ICU-onset diarrhea, of which 31 patients had CDI. The incidence of ICU-onset CDI was 25.2 cases per 10,000 ICU days. ICU-onset CDI cases had similar features with ICU-onset non-CDI diarrhea cases including the use of proton pump inhibitors and antibacterial agents. The crude mortality rate of ICU-onset CDI was 22.6%, but the attributable mortality rate of ICU-onset CDI was only 3.2% here. Toxigenic C. difficile isolates were recovered from 28 out of the 31 patients with CDI. cdtA and cdtB were found in two strains. Seventeen STs including 11 new STs were identified. All of the 11 new STs were single-locus variants of known STs and the 17 STs identified here could be clustered into 3 clades. The incidence of ICU-onset CDI here is similar to those in Europe and North America, suggesting that CDI is likely to be a common problem in China. Toxigenic C. difficile here belonged to a variety of STs, which may represent a significant clonal expansion rather than the true clonal diversity.
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Efficient CRISPR/Cas9-mediated gene editing in Arabidopsis thaliana and inheritance of modified genes in the T2 and T3 generations.
PLoS ONE
PUBLISHED: 01-01-2014
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The newly developed CRISPR/Cas9 system for targeted gene knockout or editing has recently been shown to function in plants in both transient expression systems as well as in primary T1 transgenic plants. However, stable transmission of genes modified by the Cas9/single guide RNA (sgRNA) system to the T2 generation and beyond has not been demonstrated. Here we provide extensive data demonstrating the efficiency of Cas9/sgRNA in causing modification of a chromosomally integrated target reporter gene during early development of transgenic Arabidopsis plants and inheritance of the modified gene in T2 and T3 progeny. Efficient conversion of a nonfunctional, out-of-frame GFP gene to a functional GFP gene was confirmed in T1 plants by the observation of green fluorescent signals in leaf tissues as well as the presence of mutagenized DNA sequences at the sgRNA target site within the GFP gene. All GFP-positive T1 transgenic plants and nearly all GFP-negative plants examined contained mutagenized GFP genes. Analyses of 42 individual T2 generation plants derived from 6 different T1 progenitor plants showed that 50% of T2 plants inherited a single T-DNA insert. The efficiency of the Cas9/sgRNA system and stable inheritance of edited genes point to the promise of this system for facile editing of plant genes.
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Synthesis and structure of undoped and indium-doped thermoelectric lead telluride nanoparticles.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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Undoped and indium (In)-doped lead telluride (PbTe) nanostructures were synthesized via solvothermal/hydrothermal route. The crystalline structure of the as-prepared undoped and In-doped PbTe samples was examined by X-ray diffraction (XRD) which indicated the formation of face-centered single-phase cubic crystal. A first principle calculation on indium doping shows that the indium atoms are more likely to replace lead (Pb) rather than to take the interstitial sites. Laser-induced breakdown spectroscopy (LIBS) analysis confirms that indium is incorporated into the PbTe matrix of the indium-doped PbTe samples. The effects of surfactant and synthesis temperature on the structure and morphology of the undoped PbTe were also investigated; it was found that PbTe nanostructures synthesized with the addition of surfactants exhibited uniform shapes and their size increased with the synthesis temperature.
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A promoter that drives gene expression preferentially in male transgenic rats.
Transgenic Res.
PUBLISHED: 11-27-2013
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Gender-preferential gene expression is a widespread phenomenon in humans. It is important to study how gender differences influence the pathogenesis of various diseases and response to specific drugs. The aim of this study is to determine if the mouse albumin enhancer/promoter may serve as the promoter to introduce gender-preferential gene expression in transgenic animals. We created four independent transgenic rat lines in which the human C-reactive protein transgene was under the control of mouse albumin enhancer/promoter. Quantitative real time RT-PCR analysis showed that transgene expression in the liver of male rats was significantly higher than transgene expression in the female rats (P < 0.05).There was a 5.3-fold (male/female) difference in line-519, and a 12.2-fold (male/female) difference in line-488. Enzyme-linked immunosorbent assay showed that the serum of male transgenic rats had a 13- to 679-fold difference at the protein level on transgene production compared with female transgenic rats. The male-to-female difference in gene expression was 10- to 17-fold in the liver of transgenic rats. Orchiectomy dramatically reduced protein production from the transgene in the liver. Testosterone administration into female rats did not increase the transgene expression, but estrogen administration into the male rats reduced transgene expression. This study provides a valuable tool for investigating the pathological roles of genes that are expressed in a gender-preferential manner in human disease.
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In Situ Transmission Electron Microscopy Investigation of the Electrochemical Lithiation-Delithiation of Individual Co9S8/Co-Filled Carbon Nanotubes.
ACS Nano
PUBLISHED: 11-21-2013
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Carbon nanotube (CNT)-encapsulated metal sulfides/oxides are promising candidates for application as anode materials in lithium ion battery (LIB), while their electrochemical behavior and mechanism still remain unclear. A comprehensive understanding of the lithiation mechanism at nanoscale of this type of composites will benefit the design and development of high-performance LIB materials. Here, we use Co9S8/Co nanowire-filled CNTs as a model material to investigate the lithium storage mechanism by in situ transmission electron microscopy. For a Co9S8/Co nanowire-filled closed CNT, the reaction front propagates progressively during lithiation, causing an axial elongation of 4.5% and a radial expansion of 32.4%, while the lithiated nanowire core is still confined inside the CNT. Contrastingly, for an open CNT, the lithiated Co9S8 nanowire shows an axial elongation of 94.2% and is extruded out from the open CNT. In particular, a thin graphite shell is drawn out from the CNT wall by the extruded lithiated Co9S8. The thin graphite shell confines the extruded filler and protects the filler from pulverization in the following lithiation-delithiation cycles. During multiple cycles, the Co segment remains intact while the Co9S8 exhibits a reversible transformation between Co9S8 and Co nanograins. Our observations provide direct electrochemical behavior and mechanism that govern the CNT-based anode performance in LIBs.
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Decline in platelet count after percutaneous transcatheter closure of congenital heart disease.
Acta Cardiol
PUBLISHED: 11-06-2013
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Decline in platelet count (DPC) in patients with congenital heart disease (CHD) undergoing percutaneous transcatheter closure (PTC) has seldom been reported. We sought to investigate the incidence, severity and predictors of DPC among patients with CHD undergoing PTC.
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Possible age-related hearing loss (presbycusis) and corresponding change in echolocation parameters in a stranded Indo-Pacific humpback dolphin.
J. Exp. Biol.
PUBLISHED: 11-01-2013
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The hearing and echolocation clicks of a stranded Indo-Pacific humpback dolphin (Sousa chinensis) in Zhuhai, China, were studied. This animal had been repeatedly observed in the wild before it was stranded and its age was estimated to be ~40 years. The animals hearing was measured using a non-invasive auditory evoked potential (AEP) method. Echolocation clicks produced by the dolphin were recorded when the animal was freely swimming in a 7.5 m (width)×22 m (length)×4.8 m (structural depth) pool with a water depth of ~2.5 m. The hearing and echolocation clicks of the studied dolphin were compared with those of a conspecific younger individual, ~13 years of age. The results suggested that the cut-off frequency of the high-frequency hearing of the studied dolphin was ~30-40 kHz lower than that of the younger individual. The peak and centre frequencies of the clicks produced by the older dolphin were ~16 kHz lower than those of the clicks produced by the younger animal. Considering that the older dolphin was ~40 years old, its lower high-frequency hearing range with lower click peak and centre frequencies could probably be explained by age-related hearing loss (presbycusis).
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Percutaneous device closure of ruptured sinus of valsalva aneurysm: a preliminary experience.
J Invasive Cardiol
PUBLISHED: 10-04-2013
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To evaluate the immediate and mid-term outcomes of percutaneous device closure using patent ductus arteriosus (PDA) or ventricular septal defect (VSD) occluders in patients with ruptured sinus of Valsalva aneurysm (RSVA).
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Multiple step growth of single crystalline rutile nanorods with the assistance of self-assembled monolayer for dye sensitized solar cells.
ACS Appl Mater Interfaces
PUBLISHED: 09-27-2013
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A novel multiple step growth (MSG) process has been developed to synthesize rutile nanorods (NRs) on fluorine-doped tin oxide (FTO) glass with the assistance of a self-assembled monolayer (SAM) aiming to increase the internal surface area of the 1D materials for dye sensitized solar cell (DSSC) applications. The experimental result reveals that the SAM layer can be selectively decomposed at the tip of the nanorod, namely the rutile (001) surface, due to the anisotropic photocatalytic property of the rutile. The remaining SAM layer on the side-wall of the NRs remains intact and serves as water repellent which prevents the radial growth of the NRs during the next step hydrothermal synthesis; therefore, the spacing between the NRs and the porosity of the NR array can be retained after additional growth cycles. On the other hand, introduction of a middle layer formed via TiCl4 solution treatment before the next growth cycle is found to be an effective way to control the diameters of the newly grown NRs. The performance of DSSC made from the rutile NRs grown using the MSG technique has been examined, and it is significantly affected by the internal surfaces of the NRs. Furthermore, the MSG combined with NR etching treatment by acid at low temperature (150 °C) leads to a significant enhancement in the solar cell performance. The gigantic wettability difference of the NRs before and after the SAM treatment as well as the MSG method could be adapted to prepare superhydrophobic and superhydrophilic nanostructured patterns for other applications.
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Local crystallography analysis for atomically resolved scanning tunneling microscopy images.
Nanotechnology
PUBLISHED: 09-24-2013
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Scanning probe microscopy has emerged as a powerful and flexible tool for atomically resolved imaging of surface structures. However, due to the amount of information extracted, in many cases the interpretation of such data is limited to being qualitative and semi-quantitative in nature. At the same time, much can be learned from local atom parameters, such as distances and angles, that can be analyzed and interpreted as variations of local chemical bonding, or order parameter fields. Here, we demonstrate an iterative algorithm for indexing and determining atomic positions that allows the analysis of inhomogeneous surfaces. This approach is further illustrated by local crystallographic analysis of several real surfaces, including highly ordered pyrolytic graphite and an Fe-based superconductor FeTe0.55Se0.45. This study provides a new pathway to extract and quantify local properties for scanning probe microscopy images.
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Demonstration of CRISPR/Cas9/sgRNA-mediated targeted gene modification in Arabidopsis, tobacco, sorghum and rice.
Nucleic Acids Res.
PUBLISHED: 09-02-2013
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The type II CRISPR/Cas system from Streptococcus pyogenes and its simplified derivative, the Cas9/single guide RNA (sgRNA) system, have emerged as potent new tools for targeted gene knockout in bacteria, yeast, fruit fly, zebrafish and human cells. Here, we describe adaptations of these systems leading to successful expression of the Cas9/sgRNA system in two dicot plant species, Arabidopsis and tobacco, and two monocot crop species, rice and sorghum. Agrobacterium tumefaciens was used for delivery of genes encoding Cas9, sgRNA and a non-fuctional, mutant green fluorescence protein (GFP) to Arabidopsis and tobacco. The mutant GFP gene contained target sites in its 5 coding regions that were successfully cleaved by a CAS9/sgRNA complex that, along with error-prone DNA repair, resulted in creation of functional GFP genes. DNA sequencing confirmed Cas9/sgRNA-mediated mutagenesis at the target site. Rice protoplast cells transformed with Cas9/sgRNA constructs targeting the promoter region of the bacterial blight susceptibility genes, OsSWEET14 and OsSWEET11, were confirmed by DNA sequencing to contain mutated DNA sequences at the target sites. Successful demonstration of the Cas9/sgRNA system in model plant and crop species bodes well for its near-term use as a facile and powerful means of plant genetic engineering for scientific and agricultural applications.
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Disease-modifying effect of etanercept versus sulphasalazine on spinal mobility in patients with ankylosing spondylitis.
J. Int. Med. Res.
PUBLISHED: 08-23-2013
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To model the estimated disease-modifying effect of etanercept over sulphasalazine in patients with ankylosing spondylitis.
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Prevalence and risk factors of urinary incontinence for post-stroke inpatients in Southern China.
Neurourol. Urodyn.
PUBLISHED: 08-18-2013
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The prevalence and risk factors of urinary incontinence (UI) for post-stroke inpatients remain unclear. In this study, we aimed to investigate the risk factors associated with the development of UI for post-stroke inpatients in southern China.
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Intrinsic electronic and transport properties of graphyne sheets and nanoribbons.
Nanoscale
PUBLISHED: 08-15-2013
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Graphyne, a two-dimensional carbon allotrope like graphene but containing doubly and triply bonded carbon atoms, has been proven to possess amazing electronic properties as graphene. Although the electronic, optical, and mechanical properties of graphyne and graphyne nanoribbons (NRs) have been previously studied, their electron transport behaviors have not been understood. Here we report a comprehensive study of the intrinsic electronic and transport properties of four distinct polymorphs of graphyne (?, ?, ?, and 6,6,12-graphynes) and their nanoribbons (GyNRs) using density functional theory coupled with the non-equilibrium Greens function (NEGF) method. Among the four graphyne sheets, 6,6,12-graphyne displays notable directional anisotropy in the transport properties. Among the GyNRs, those with armchair edges are nonmagnetic semiconductors whereas those with zigzag edges can be either antiferromagnetic or nonmagnetic semiconductors. Among the armchair GyNRs, the ?-GyNRs and 6,6,12-GyNRs exhibit distinctive negative differential resistance (NDR) behavior. On the other hand, the zigzag ?-GyNRs and zigzag 6,6,12-GyNRs exhibit symmetry-dependent transport properties, that is, asymmetric zigzag GyNRs behave as conductors with nearly linear current-voltage dependence, whereas symmetric GyNRs produce very weak currents due to the presence of a conductance gap around the Fermi level under finite bias voltages. Such symmetry-dependent behavior stems from different coupling between ?* and ? subbands. Unlike ?- and 6,6,12-GyNRs, both zigzag ?-GyNRs and zigzag ?-GyNRs exhibit NDR behavior regardless of the symmetry.
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Gene expression analysis in response to osmotic stimuli in the intervertebral disc with DNA microarray.
Eur. J. Med. Res.
PUBLISHED: 06-27-2013
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Intervertebral disc (IVD) cells experience a broad range of physicochemical stimuli under physiologic conditions, including alterations in their osmotic environment. At present, the molecular mechanisms underlying osmotic regulation in IVD cells are poorly understood. This study aims to screen genes affected by changes in osmotic pressure in cells of subjects aged 29 to 63 years old, with top-scoring pair (TSP) method.
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Associations between inflammation, nocturnal back pain and fatigue in ankylosing spondylitis and improvements with etanercept therapy.
J. Int. Med. Res.
PUBLISHED: 06-26-2013
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To investigate the relationships between inflammation, nocturnal back pain and fatigue in ankylosing spondylitis (AS) and the impact of 12 weeks etanercept treatment versus sulfasalazine or placebo.
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O-Demethylations catalyzed by Rieske nonheme iron monooxygenases involve the difficult oxidation of a saturated C-H bond.
ACS Chem. Biol.
PUBLISHED: 06-10-2013
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Dicamba monooxygenase (DMO) catalyzes the O-demethylation of dicamba (3,6-dichloro-2-methoxybenzoate) to produce 3,6-dichlorosalicylate and formaldehyde. Recent crystallographic studies suggest that DMO catalyzes the challenging oxidation of a saturated C-H bond within the methyl group of dicamba to form a hemiacetal intermediate. Testing of this hypothesis was made possible by our development of two new independent techniques. As a novel method to allow use of (18)O2 to follow reaction products, bisulfite was used to trap newly formed (18)O-formaldehyde in the stable adduct, hydroxymethanesulfonate (HMS(-)), and thereby prevent the rapid exchange of (18)O in formaldehyde with (16)O in water. The second technique utilized unique properties of Pseudomonas putida formaldehyde dehydrogenase that allow rapid conversion of (18)O-formaldehyde into stable and easily detectable (18)O-formic acid. Experiments using these two new techniques provided compelling evidence for DMO-catalyzed oxidation of the methyl group of dicamba, thus validating a mechanism for DMO [and for vanillate monooxygenase, a related Rieske nonheme iron monooxygenase] that involves the difficult oxidation of a saturated C-H bond.
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Ten cancer associated genes identified in peripheral blood mononuclear cells from patients with pancreatic adenocarcinoma.
Hepatogastroenterology
PUBLISHED: 06-05-2013
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Identification of biomarkers for pancreatic cancer may help diagnosis and treatment of patients.
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Comparison of effects of thoracic epidural and intravenous administration of lidocaine on target-controlled infusion of propofol and tracheal intubation response during induction of anesthesia.
J. Cardiothorac. Vasc. Anesth.
PUBLISHED: 05-22-2013
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To compare the effects of thoracic epidural anesthesia (TEA) and intravenous (IV) lidocaine on the effect-site concentration (Ce) of propofol target-controlled infusion (TCI) and the intubation-induced stress responses during general IV anesthesia induction.
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Generation of a phage-display library of single-domain camelid VH H antibodies directed against Chlamydomonas reinhardtii antigens, and characterization of VH Hs binding cell-surface antigens.
Plant J.
PUBLISHED: 05-18-2013
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Single-domain antibodies (sdAbs) are powerful tools for the detection, quantification, purification and subcellular localization of proteins of interest in biological research. We have generated camelid (Lama pacos) heavy chain-only variable VH domain (VH H) libraries against antigens in total cell lysates from Chlamydomonas reinhardtii. The sdAbs in the sera from immunized animals and VH H antibody domains isolated from the library show specificity to C. reinhardtii and lack of reactivity to antigens from four other algae: Chlorella variabilis, Coccomyxa subellipsoidea, Nannochloropsis oceanica and Thalassiosira pseudonana. Antibodies were produced against a diverse representation of antigens as evidenced by sera ELISA and protein-blot analyses. A phage-display library consisting of the VH H region contained at least 10(6) individual transformants, and thus should represent a wide range of C. reinhardtii antigens. The utility of the phage library was demonstrated by using live C. reinhardtii cells to pan for VH H clones with specific recognition of cell-surface epitopes. The lead candidate VH H clones (designated B11 and H10) bound to C. reinhardtii with EC50 values ? 0.5 nm. Treatment of cells with VH H B11 fused to the mCherry or green fluorescent proteins allowed brilliant and specific staining of the C. reinhardtii cell wall and analysis of cell-wall genesis during cell division. Such high-complexity VH H antibody libraries for algae will be valuable tools for algal researchers and biotechnologists.
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[Effectiveness of minimally invasive transforaminal lumbar interbody fusion assisted with microscope in treatment of lumbar degenerative disease].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-16-2013
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To investigate the effectiveness of minimally invasive transforaminal lumbar interbody fusion (TLIF) assisted with microscope for lumbar degenerative disease.
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Laparotomy versus retroperitoneal laparoscopy in debridement and drainage of retroperitoneal infected necrosis in severe acute pancreatitis.
Surg Endosc
PUBLISHED: 05-10-2013
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The aim of this study was to compare laparotomy and retroperitoneal laparoscopy in debridement and drainage of retroperitoneal infected necrosis of severe acute pancreatitis (SAP), and to evaluate the curative efficacy and the timing of retroperitoneal laparoscopic debridement drainage (RLDD) for SAP patients.
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The integrated design and optimization of a WEEE collection network in Shanghai, China.
Waste Manag Res
PUBLISHED: 05-07-2013
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An integrated formal collection and recycling network is a significant concern to achieve efficient management of waste electrical and electronic equipment (WEEE). This study, which aimed to investigate the present problems of WEEE recycling in China, proposes the application of a comprehensive solution approach to address a complete WEEE collection and transportation network in Shanghai, China. The methodologic steps regard three things: identification of WEEE collection sites and transit sites with quadratic optimizing models solved by exact algorithm; vehicle routing planning with a modified ant colony algorithm; and defining of minimum transportation cycles and proper shipping arrangements. The rounded WEEE collection network is presented as technical support and a demonstration of further planning and construction of the WEEE recycling system in China.
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Osteosarcoma around the knee treated with neoadjuvant chemotherapy and a custom-designed prosthesis.
Orthopedics
PUBLISHED: 04-18-2013
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This article describes a novel approach using high-dose neoadjuvant chemotherapy with wide tissue resection and a specially designed artificial joint in 104 patients with stage IIB osteosarcoma near the knee. Sixty-four lesions were located at the distal femur, 39 at the proximal tibia, and 1 invaded the proximal tibia from the distal femur. Pathological fracture was present in 9 patients. Three courses of high-dose methotrexate, doxorubicin, and ifosfamide were administered preoperatively, and 6 courses were administered postoperatively. Preoperative radiographs and magnetic resonance images were obtained to determine the required tumor resection range and prosthesis size. Osteotomy of 3 cm of normal bone outside the tumor and wide resection of normal peripheral soft tissue were performed. Reconstruction with a rotary hinge or simple hinge prosthesis, as appropriate, was then performed. The Musculoskeletal Tumor Society 93 scoring system was used to evaluate limb function 6 months postoperatively. At final follow-up, recurrence, complication, survival, and amputation rates were 4%, 18%, 85%, and 4%, respectively. No recurrences were observed at the ends of amputated bones. Complications included infection (6%), nerve injury (3%), and prosthesis-related events (2% dislocation, 3% breakage, and 1% dislocation-related). Mean Musculoskeletal Tumor Society 93 score was 28 points, which indicated an excellent functional outcome. The low recurrence rate is attributed to the efficacy of the chemotherapy and the accuracy of the margin of resection.Effective chemotherapy reduces the risk of tumor metastasis and clarifies the tumor margin. Accurate identification of the resection margin reduces the risk of local recurrence.
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Effect and mechanism of propofol on myocardial ischemia reperfusion injury in type 2 diabetic rats.
Microvasc. Res.
PUBLISHED: 04-14-2013
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Propofol has been reported to have an inhibitory effect on ischemia/reperfusion (I/R) injury in various experimental models by reducing oxidative stress, protecting mitochondrial function and suppressing apoptosis. The aim of this study was to investigate the effect and mechanism of propofol on myocardial I/R injury in type 2 diabetic rats.
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Atomically resolved spectroscopic study of Sr2IrO4: experiment and theory.
Sci Rep
PUBLISHED: 04-11-2013
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Particularly in Sr2IrO4, the interplay between spin-orbit coupling, bandwidth and on-site Coulomb repulsion stabilizes a J(eff) = 1/2 spin-orbital entangled insulating state at low temperatures. Whether this insulating phase is Mott- or Slater-type, has been under intense debate. We address this issue via spatially resolved imaging and spectroscopic studies of the Sr2IrO4 surface using scanning tunneling microscopy/spectroscopy (STM/S). STS results clearly illustrate the opening of an insulating gap (150 ~ 250 meV) below the Néel temperature (TN), in qualitative agreement with our density-functional theory (DFT) calculations. More importantly, the temperature dependence of the gap is qualitatively consistent with our DFT + dynamical mean field theory (DMFT) results, both showing a continuous transition from a gapped insulating ground state to a non-gap phase as temperatures approach TN. These results indicate a significant Slater character of gap formation, thus suggesting that Sr2IrO4 is a uniquely correlated system, where Slater and Mott-Hubbard-type behaviors coexist.
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Associations between single-nucleotide polymorphisms and epidural ropivacaine consumption in patients undergoing breast cancer surgery.
Genet Test Mol Biomarkers
PUBLISHED: 04-11-2013
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Up to date, few published studies indicated the associations between genetic polymorphisms and epidural local anesthetics consumption. In this study, we investigated the associations between seven single-nucleotide polymorphisms (SNPs) and epidural ropivacaine consumption during breast cancer surgery in women from northeastern China. These seven SNPs (rs3803662 and rs12443621 in TNCR9, rs889312 in MAP3K1, rs3817198 in LSP1, rs13387042 at 2q35, rs13281615 at 8q24, and rs2046210 at 6q25.1) were identified by recent genome-wide association studies associated with tumor susceptibility. A total of 418 breast cancer women received thoracic epidural anesthesia with ropivacaine for elective mastectomy with axillary clearance. Their blood samples were genotyped for the seven SNPs using the SNaPshot method. For SNP rs13281615, the subjects with genotype AG and GG consumed a greater amount of the total epidural ropivacaine and the mean ropivacaine dose than the subjects with genotype AA (p=0.047 and p=0.003, respectively). Furthermore, no statistical differences were found in the total dose of ropivacaine, the mean consumption of ropivacaine, the onset of ropivacaine, or the initial dose of lidocaine among the three genotypic groups for the other six SNPs studied. Our study indicated that SNP rs13281615 at 8q24 was associated with the consumption of epidural ropivacaine during breast cancer surgery in northeastern Chinese women. It might provide new insights into the mechanisms of ropivacaine action and metabolism and facilitate the development of personalized medicine.
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Synthesis and characterization of biotin modified cholesteryl pullulan as a novel anticancer drug carrier.
Carbohydr Polym
PUBLISHED: 04-06-2013
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A series of biotin modified cholesteryl pullulan (Bio-CHSP) conjugates with different degrees of substitution (DS) of biotin moiety were synthesized and characterized by Fourier transform infrared (FT-IR), proton nuclear magnetic resonance ((1)H NMR) and X-ray diffraction (XRD). Bio-CHSP conjugates were amphiphilic in nature and their self-aggregation behavior in aqueous media was evaluated by the fluorescence probe technique. Bio-CHSP self-aggregated nanoparticles (Bio-CHSP NPs) were prepared and analyzed by dynamic light scattering (DLS), zeta potential and transmission electron microscopy (TEM) technologies. These novel nanoparticles were almost spherical in shape, and their size, ranging from 178.8 to 100.0nm. The safety of Bio-CHSP NPs was studied through single dose toxicity test in mice, and the result showed that Bio-CHSP NPs were well tolerated at the intravenous dose of 200mg/kg in mice. Moreover, as a model anticancer drug, mitoxantrone loaded Bio-CHSP NPs were also prepared and characterized in this study.
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Retroperitoneal laparoscopic debridement and drainage of infected retroperitoneal necrosis in severe acute pancreatitis.
Asian J Surg
PUBLISHED: 04-03-2013
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To explore the effect of retroperitoneal laparoscopic debridement and drainage on infected necrosis in severe acute pancreatitis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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