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Hepatitis B virus surface antigen (HBsAg), a specific antigen on the membrane of hepatitis B virus (HBV)-infected cells, provides a perfect target for therapeutic drugs. In order to mediate successful targeted delivery of these therapies, it is essential to have antibodies that recognize HBsAg with high specificity and affinity. In this report, we constructed a natural immune antigen binding fragments (Fab) antibody phage display library against HBsAg and after three rounds of panning, five Fab fragments with significant HBsAg binding ability were selected and analysed. DNA sequencing revealed that all the light chains had the same sequence, while all the Fd genes exhibited different sequences. For further application, all of the Fab antibodies were reconstructed into single chain antibodies (scFvs) and expressed in Escherichia coli BL21 cells. Indirect enzyme-linked immunosorbent assay analysis demonstrated that all five scFvs maintained a high affinity for HBsAg and could bind HBsAg on the membrane of HBV-infected cells. Indirect fluorescent staining analysis revealed that one of the scFvs (scFv15) could be internalized into HBsAg-positive HepG2.2.15 cells through clathrin-mediated endocytosis pathway. The internalizing scFv15 antibody would have great potential for the targeted delivery of therapeutics to HBV-infected cells. [ABSTRACT FROM AUTHOR]

Completely biodegradable foams of poly(propylene carbonate) (PPC) derived from carbon dioxide and propylene oxide were fabricated using N, N′-dinitroso pentamethylene tetramine (DPT) as chemical blowing agent, and urea as the activator to lower the decomposition temperature of DPT. Thermal decomposition behavior and gas evolution behavior of the DPT composite with various urea to DPT ratios were investigated to optimize the composition of the blowing agent. The formulation of blowing agent mixture and foaming condition, the foam morphologies, the molecular weight change, as well as the mechanical properties of produced PPC foams were studied extensively. The experimental results demonstrated that the greatest blowing ratio of 14.8 can be afforded in case 12 phr blowing agent was used at 170 °C for 30 min. Gel permeation chromatography (GPC) and thermal analysis revealed that DPT acted as both chain-extension agent and blowing agent for PPC matrix. The molecular weight of PPC subjected to foaming increased by 76%. The foamed PPC exhibited superior mechanical properties and can be used as packaging material for many practical applications. [ABSTRACT FROM AUTHOR]

VEGF-A is important in tumor angiogenesis. and a humanized anti-VEGF-A monoclonal antibody (bevacizumab) has been approved by the FDA as a treatment for metastatic colorectal and nonsquamous, non-small-cell lung cancer in combination with chemotherapy. However, contributions of both tumor- and stromal-cell derived VEGF-A to vascularization of human tumors grown in immunodeficient mice hindered direct comparison between the pharmacological effects of anti-VEGF antibodies with different abilities to block host VEGF. Therefore, by gene replacement technology, we engineered mice to express a humanized form of VEGF-A (hum-X VEGF) that is recognized by many anti-VEGF antibodies and has biochemical and biological properties comparable with WT mouse and human VEGF-A. The hum-X VEGF mouse model was then used to compare the activity and safety of a panel of VEGF Mabs with different affinities for VEGF-A. Although in vitro studies clearly showed a correlation between binding affinity and potency at blocking endothelial cell proliferation stimulated by VEGF, in vivo experiments failed to document any consistent correlation between antibody affinity and the ability to inhibit tumor growth and angiogenesis in most animal models. However, higher-affinity antibodies were more likely to result in glomerulosclerosis during long-term treatment. [ABSTRACT FROM AUTHOR]

Mechanical and thermal properties of poly(arylene disulfide) synthesized by ring-opening reaction of cyclic(aromatic disulfide) oligomer were reported. These oligomers were prepared from 4,4′-oxybis(benzenethiol). Three-point bending tests were performed to measure the flexural properties of the poly(arylene disulfide). DSC and TGA techniques were used to characterize the thermal properties of these polymers. Ring-opening reactions were carried out by hot-press under atmosphere and nitrogen atmosphere, respectively. Oxidation reaction of these polymers was detected from Raman spectra under atmosphere. The glass transition temperature increased but 10% weight loss temperature decreased with increasing ring-opening temperature. The flexural strength decreased with increasing the temperature of ring-opening polymerization under both atmosphere and nitrogen atmosphere. The polydisulfides could be used as high temperature and thermally curing insulating materials to substitute epoxy resins. [ABSTRACT FROM AUTHOR]

As an on-going project to synthesise the copolymers of epoxides with carbon dioxide, the ternary polymerisation of propylene oxide and ethylene oxide with carbon dioxide was investigated using an anaerobic system. The terpolymerisation of propylene oxide and ethylene oxide with carbon dioxide was carried out with supported zinc glutarate catalyst, consequently producing high molecular weight poly(propylene-ethylene carbonate) (PPEC). The structure and properties of PPEC were studied by means of gel permeation chromatographic (GPC) analysis, Fourier Transform infrared (FTIR), nuclear magnetic resonance (NMR) spectroscopy, different scanning calorimetry (DSC), and thermogravimetric analysis (TGA) techniques. NMR and FTIR results showed that the terpolymer PPEC was a polycarbonate consisting of propylene carbonate and ethylene carbonate together with random ether linkages. The glass transition temperature (Tg) of the terpolymers decreased with increasing ethylene oxide (EO) content. TGA analysis indicated high thermal stability for the synthesised terpolymer. [ABSTRACT FROM AUTHOR]

The Institute for Clinical and Economic Review (ICER), is an independent research organization in the US, that performs cost-effectiveness and budget impact analyses for pharmaceuticals. The UK and Canada drug prices are much closer to, or under, the threshold prices estimated by ICER using the $100,000 threshold. [Extracted from the article]

The silkworm has become an ideal multicellular eukaryotic model system for basic research. The major advantages of expressing foreign genes in silkworm larvae are the low cost of feeding, the extremely high levels of expression achievable compared with expression in cell lines and increased safety because the baculovirus is noninfectious to vertebrates. In this study, we used a recently developed Bombyx mori Nucleopolyhedrovirus (BmNPV) bacmid to express the spider flagelliform silk gene in silkworm larvae. The recombinant bacmid baculoviruses (rBacmid/BmNPV/Flag) were introduced into the first-day larvae of the fifth instar by subcutaneous injection. The worms presented symptoms typical of NPV infection from 72 h after injection compared with control. The haemolymph was collected from the infected larvae 120 h post-infection and the recombinant 6× His-tagged Flag protein was purified by the Ni-NTA spin kit under denaturing conditions with 8 m urea. A 37.0-kDa protein was visualized both in rBacmid/BmNPV/Flag-infected haemolymph and eluting fraction. The results showed that the Bac-to-Bac/BmNPV baculovirus expression system is an efficient tool to express the target gene in silkworm larvae, which takes only 7–10 days for generating recombinant baculovirus, compared with the traditional homologous recombination method, which needs at least 40 days for multiple rounds of purification and amplification of viruses. [ABSTRACT FROM AUTHOR]

Resveratrol, a natural polyphenolic phytoalexin, has been considered as a potential anti-inflammatory agent because of its suppressive effect on nuclear factor-κB (NF-κB). However, we recently found that treatment of glomerular mesangial cells with resveratrol significantly and dose-dependently enhanced NF-κB activation triggered by proinflammatory cytokines. This finding was evidenced by different reporter assays as well as by expression of an endogenous NF-κB-dependent gene, intercellular adhesion molecule-1. The NF-κB promoting effect of resveratrol was also observed in renal tubular LLCPK1 cells, but not in HepG2 hepatoma cells. In all cell types tested, treatment with resveratrol alone did not affect NF-κB activity. The enhanced activation of NF-κB by resveratrol progressed for at least 24 h and was accompanied by sustained down-regulation of an endogenous NF-κB inhibitor, IκBβ, but not IκBα. Although expression of inducible nitric oxide synthase was suppressed by resveratrol, nitric oxide, a negative regulator of NF-κB, was not involved in the regulation of NF-κB by resveratrol. These data elucidated, for the first time, that resveratrol may enhance activation of NF-κB under certain circumstances. [ABSTRACT FROM AUTHOR]

Abstract: Rituxan, a chimeric anti-CD20 antibody, has been used for treating non-Hodgkin''s lymphoma and some autoimmune diseases. However, a humanized anti-CD20 antibody is desirable for long-term treatment of autoimmune diseases. CD20 is an integral membrane protein with a small intervening extracellular loop. Lacking a native soluble CD20 protein, we developed a simple cell-based enzyme-linked immunosorbent assay (ELISA) using live WIL2 cells in a 96-well format to measure relative binding affinity to support the humanization process. Although WIL2 cells grow in suspension and require centrifugation during the wash steps, the assay was quantitative and reproducible. We also demonstrated that cloned adherent transfected Chinese hamster ovary (CHO) cells could be used to improve assay throughput. For clinical studies requiring quantification of the humanized antibody in serum, we used an alternate approach and developed a high throughput ELISA using an anti-idiotypic antibody as a surrogate antigen for capture and an anti-idiotypic antibody for detection to overcome serum effects. These assay strategies may be applied for characterization of other antibodies directed to multitransmembrane proteins. [Copyright &y& Elsevier]

We have constructed a medium density physical map of bovine chromosome 19 using a combination of mapping loci on both a bovine bacterial artificial chromosome (BAC) scaffold map and a whole genome radiation hybrid (WGRH) panel. The resulting map contains 70 loci spanning the length of bovine chromosome 19. Three contiguous groups of BACs were identified on the basis of multiple loci mapping to individual BAC clones. Bovine chromosome 19 was found in this study to be comprised almost entirely from regions of human chromosome 17, with a small region putatively assigned to human chromosome 10. Fourteen breakpoints between the bovine and human chromosomes were detected, with a possibility of five more based on ordering of the WGRH map. Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

T cell immunity to lytic proteins of herpesviruses is important in host control of infection. We have characterized the cytotoxic T lymphocyte (CTL) response to 5 human herpesvirus 8 (HHV-8) homologues of lytic proteins in HHV-8-seropositive individuals. HLA class I-restricted, CD8(+) CTL responses to >/=1 HHV-8 lytic protein were detected in all 14 HHV-8-seropositive study subjects tested, with or without human immunodeficiency virus type 1 (HIV-1) infection, but not in any of 5 HHV-8-seronegative individuals. Seven of these study subjects with both HHV-8 and HIV-1 infection had greater anti-CTL reactivity to glycoprotein H (open-reading frame 22) than did the 7 study subjects infected only with HHV-8. Moreover, there was a strong, inverse correlation between HIV-1 load and glycoprotein H-specific CTL lysis in the study subjects infected with both viruses. CTL reactivity to HHV-8 lytic proteins may be involved in host control of HHV-8-related diseases, such as Kaposi's sarcoma. [ABSTRACT FROM AUTHOR]

This paper presents a Raman spectroscopic study of compositional-change-induced structure variation and of the related mechanism of Mg doping in LiSbO3 (LS)-modified (K0.5Na0.5)NbO3 (KNN) ceramics. With increasing LS content from 0 to 0.06, a discontinuous shift towards higher wavenumbers was found for the band position of the A1g(v1) stretching mode of KNN, accompanied by a clearly nonlinear broadening of this band and a decrease in its intensity. Such morphological changes in the Raman spectrum result from two factors: (i) changes in polarizability/binding strength of the O-Nb-O vibration upon incorporation of Li ions in the KNN perovskitic structure and (ii) a polymorphic phase transition (PPT) from orthorhombic to tetragonal (O - T) phase at x > 0.04. Upon increasing the amount, w, of Mg dopant incorporated into the (1-x)KNN-xLS ceramic structure, the intensity of the Raman bands are enhanced, while the peak position and the full width at half maximum of the A1g(v1) mode was found to experience a clear dependence on both w and x. Raman characterization revealed that the mechanism of Mg doping is strongly correlated with the concentration of Li in the perovskite structure: Mg2+ ions will preferentially replace Li+ ions for low Mg doping while replace K/Na ions for higher doping of Mg. The PPT O - T was also found to be altered by the introduction of Mg and the critical value of LS concentration, xO[?]T, for incipient O - T transition in the KNN-xLS-wMT system was strongly dependent on Mg content, with xO - T being roughly equal to 0.04 + 2w, for the case of dilute Mg alloying. [ABSTRACT FROM AUTHOR]

An abstract of the conference paper "Prenatal screen the abnormal flexed direction of knee joints using the parallel moving examination," by M. Qian and colleagues is presented.

Development of safe electrolytes that are compatible with both lithium metal anodes and high-voltage cathodes that can operate in a wide-temperature range is a formidable, yet important challenge. Recently, a new class of electrolytes based on liquefied gas solvents has shown promise in addressing this issue. Concerns, however, have been raised on the pressure, flammability and low maximum operating temperature of these systems. Here, we endeavor to mitigate safety and practicality concerns by demonstrating an enhanced safety feature inherent in liquefied gas electrolytes and by showing the viability of using difluoromethane as a liquefied gas solvent which has lower pressure, lower flammability, and improved maximum operation temperature characteristics compared with fluoromethane. We create a custom-built setup to enable liquefied gas electrolyte characterization through Raman spectroscopy and supplement this with molecular dynamics (MD) simulations. The electrolyte shows good conductivity through a wide temperature range and compatibility with both the lithium metal anode and 4 V class cathodes. The demonstrated use of such alternative liquefied gas solvents opens a path towards the further development of high-energy and safe batteries that can operate in a wide-temperature range. • Demonstration of unique safety feature inherent to liquefied gas electrolytes. • Low flammability, difluoromethane based solvent enables wide temperature operation. • Raman spectroscopy reveals few free co-solvent molecules and high salt aggregation. • MD simulations compliment experimental results with insight into Li+ transportation. • Li.|Cu plating/stripping and full cells operational through a wide temperature range [ABSTRACT FROM AUTHOR]

Prognosis in patients with myelodysplastic syndromes (MDS) is closely correlated with cytopenia. To date, no factor is available which is able to reliably stimulate megakaryopoiesis in vivo. Recently, the ligand of the mpl receptor was cloned and found to be thrombopoietin (TPO). We measured endogenous TPO serum levels in 69 patients suffering from MDS using an TPO receptor-based ELISA. Twenty-six of the patients suffered from refractory anemia (RA), 12 from RA with excess of blasts (RAEB), 25 from RAEB in transition (RAEBt), and six from chronic myelomonocytic leukemia (CMML). This assay uses a chimeric molecule consisting of the human TPO receptor fused to the Fc portion of human IgG as the capture reagent. Biotinylated antibody to TPO IgG was used for detection and the lower detection limit in serum was found to be 160 pg/ml. Samples obtained from healthy individuals with a normal platelet number were shown to be below detectable levels. In patients with RA, high endogenous serum TPO concentrations correlated with low platelet count and significantly elevated TPO concentrations were only found when megakaryopoiesis was absent or decreased in the bone marrow. This correlation was not detected in RAEB and RAEBt patients and no detectable TPO serum concentrations were found in six CMML patients whether they showed decreased or normal platelet count. Our data show that endogenous TPO production is upregulated by decreased circulating platelet count only in patients with refractory anemia. In the more advanced stages of MDS where the leukemic clone has further progressed, an inadequate TPO response occurs, possibly due to overexpression of the mpl receptor by the malignant clone. [ABSTRACT FROM AUTHOR]

CoO/Fe thin films were grown epitaxially onto vicinal Ag(001) and investigated using magneto-optic Kerr effect, x-ray magnetic circular dichroism (XMCD), and x-ray magnetic linear dichroism (XMLD) techniques. We show that the CoO film in the ultrathin regime does not induce a uniaxial magnetic anisotropy but a coercivity enhancement. This result provides a mechanism for the microscopic origin of the rotatable magnetic anisotropy. XMLD measurement further reveals that the underlying mechanism is that the CoO spins are totally rotatable in the ultrathin regime to follow the Fe magnetization. [ABSTRACT FROM AUTHOR]

In Ge2Sb2Te5 (GST), the prototype phase-change alloy for data storage, in situ x-ray diffraction experiments reveal a pressure-induced crystalline-amorphous-crystalline transition sequence, all at the same fixed composition and in one experimental cycle. A body-centered-cubic polymorph is discovered at high pressures; the formation of this phase is attributable to its high packing density rendered possible by the switch from covalent to metallic bonding as predicted by ab initio calculations. [ABSTRACT FROM AUTHOR]

IgG antibodies have been used to treat many diseases including cancer. IgG antibody-drug conjugates (ADCs) deliver cytotoxic drugs to target cells for cell elimination, but they have dose limiting toxicity due to target-independent uptake, including pinocytotic uptake. Neonatal Fc receptor (FcRn) recycles pinocytosed IgG in a pH-dependent manner and is the receptor responsible for the long half-life of IgG. Use of IgG variants with stronger FcRn binding at pH 6.0 for ADCs might improve recycling efficiency and reduce toxicity. However, these variants have residual FcRn binding at pH 7.4, which could lead to FcRn-mediated uptake and higher toxicity. Thus, the uptake of such variants at pH 7.4 needs to be evaluated. Here we report a reproducible and quantitative assay using an inducible HM7 colorectal cancer cell line to measure IgG uptake at endogenous and overexpressed FcRn levels. Our assay had comparable reproducibility at pH 6.0, 6.8 and 7.4. The wild type (WT) IgG had similar uptake at endogenous and overexpressed FcRn levels, as expected for pinocytotic uptake. We found similar uptake of a WT IgG and a stronger FcRn binding T307Q/N434A variant (QA variant) at endogenous FcRn levels at pH 7.4, although the QA variant had higher uptake at overexpressed FcRn levels. The QA variant also had higher uptake than the WT IgG at overexpressed FcRn levels at pH 6.8. Our assay can be used to characterize the stronger FcRn binding variants to aid in selection of suitable variants with low uptake at pH 7.4 for use as ADCs. [ABSTRACT FROM AUTHOR]

The lower mantle is believed to contain much less hydrogen (or H 2 O) because of the low storage capacity of the dominant mineral phases, such as bridgmanite and ferropericlase. However, possible hydrogen storage in the third most abundant mineral in the region, CaSiO 3 perovskite (Ca-Pv), is not well unknown. We have synthesized Ca-Pv from different starting materials with varying H 2 O contents at 19–120 GPa and 1400–2200 K in laser-heated diamond-anvil cell. While cubic perovskite structure is stable at the mantle-related pressures-temperatures (P − T) in anhydrous systems, we found non-cubic diffraction peak splitting in Ca-Pv even at high temperatures when it is synthesized from hydrous starting materials. In-situ high-pressure infrared spectroscopy showed OH vibration possibly from Ca-Pv. The unit-cell volume of hydrothermally synthesized Ca-Pv is systematically smaller than that of anhydrous Ca-Pv at high pressures. These observations suggest possible H 2 O storage in Ca-Pv at mantle-related P − T conditions. We also found the formation of separate δ –AlOOH and Ca-Pv phases from Al-bearing CaSiO 3 glass starting materials in an H 2 O medium at 60 GPa and 1400 K. Ca-Pv still showed non-cubic peak splitting at high temperatures in this experiment. Therefore, it is possible that hydrous phases may coexist together with hydrous Ca-Pv in the lower mantle. • Water alters the crystal structure and properties of CaSiO 3 perovskite. • Hydrous CaSiO 3 perovskite has a tetragonal structure at mantle-related high temperatures. • Al separates from CaSiO 3 perovskite and forms delta-AlOOH at mantle-related pressures. [ABSTRACT FROM AUTHOR]

The article summarizes research published in an online article on the relation between prefrontal circuit dysfunction and antidepressant-induced dedritic spine formation.

Boron carbide (B4C) coatings are prepared by an RF inductively coupled plasma (ICP) torch with different amounts of hydrogen introduced into the sheath gas. The effects of the added hydrogen on the characteristics of the plasma are diagnosed by optical emission spectroscopy and high speed photography. The effects on the melting of B4C particles in the plasma are studied by scanning electron microscopy (SEM). The microstructure of the B4C coatings was determined with SEM imaging and x-ray diffraction analysis. The results show that adding hydrogen to the sheath gas leads to plasma contraction, which results in higher gas temperature of plasma. It also enhances B4C particles spheroidizing and improves the compactness of B4C coatings. Plasma processing does not change the main phase of boron carbide. The obtained results on B4C coatings on Cu substrates allows for improving the B4C coatings fabrication process. [ABSTRACT FROM AUTHOR]

Quantum confinement permits the existence of multiple terahertz magnon modes in atomically engineered ultrathin magnetic films and multilayers. By means of spin-polarized high-resolution electron energy-loss spectroscopy, we report on the direct experimental detection of all exchange-dominated terahertz confined magnon modes in a 3 ML Co film. We demonstrate that, by tuning the structural and magnetic properties of the Co film, through its epitaxial growth on different surfaces, e.g., Ir(001), Cu(001), and Pt(111), one can achieve entirely different in-plane magnon dispersions, characterized by positive and negative group velocities. Our first-principles calculations show that spin-dependent many-body correlation effects in Co films play an important role in the determination of the energies of confined magnon modes. Our results suggest a pathway towards the engineering of the group velocity of confined ultrafast magnons. [ABSTRACT FROM AUTHOR]

The article presents a study conducted by Cyrus S. Rustomji and colleagues which evaluates the performance of liquefied gas electrolytes for electrochemical energy storage devices. It mentions the use of hydrofluorocarbon solvents to allow for a superior solvent dielectric-fluidity factor higher than commonly used solvents and study of electrochemical capacitors with liquefied gas electrolyte based on difluoromethane have similar resistance and capacitance to conventional devices.

The article discusses report of aphelenchoides besseyi causing white tip disease of rice in Jilin Province of China, by researchers including S. Q. On and J. Gao from Laboratory of Plant Pathology, Department of Plant Protection, Jilin Agricultural University in Jilin, China.

A response from the authors of the article "Systematic review and economic evaluation of cilostazol, naftidrofuryl oxalate, pentoxifylline and inositol nicotinate for the treatment of intermittent claudication in people with peripheral arterial disease" in a 2011 issue is presented.

An abstract of the research paper "Comparison of color Doppler ultrasound and pathology in endometrial cancer and endometrial hyperplasia," by D. Zhang and colleagues is presented.

In order to probe the changes in the valence state and magnetic properties of Eu metal under extreme pressure, x-ray absorption near-edge spectroscopy, x-ray magnetic circular dichroism, and synchrotron Mössbauer spectroscopy experiments were carried out. The Mössbauer isomer shift exhibits anomalous pressure dependence, passing through a maximum near 20 GPa. Density functional theory has been applied to give insight into the pressure-induced changes in both Eu's electronic structure and Mössbauer isomer shift. Contrary to previous reports, Eu is found to remain nearly divalent to the highest pressures reached (87 GPa) with magnetic order persisting to at least 50 GPa. These results should lead to a better understanding of the nature of the superconducting state found above 75 GPa and of the sequence of structural phase transitions observed to 92 GPa. [ABSTRACT FROM AUTHOR]

An abstract of the article "Effects of the breast ultrasound types for detection of mammary lesion in females," by D. Zhang and colleagues is presented.

In title compound, [Er(C12H9O2)2(C12H8N2)2(H2O)2](C12H9O2)·H2O, the carboxyl groups have only a monodentate coordination mode. The ErIII atom is eight-coordinated in a distorted dodecahedral environment by four O and four N atoms from two 1-naphthaleneacetic acid (NAA) ligands, two aqua ligands and two 1,10-phenanthroline (phen) ligands. A twofold rotation axis passes through Er. The molecules are linked into sheets by O—H...O and C—H...O hydrogen bonds. There is disorder in the anion and in the solvent water molecule; the site occupancies were set equal to 0.5. [ABSTRACT FROM AUTHOR]

The title compound, C22H23NO5, crystallizes with two independent molecules in the asymmetric unit. In one molecule, the dihedral angle between one outer ring and the central ring is 86.37 (10)°, while that between the two outer rings is 88.99 (10)°; in the other molecule, these angles are 87.37 (9) and 88.14 (9)°, respectively. The molecules are linked into two chains by a combination of O—H...O and C—H...O hydrogen bonds. [ABSTRACT FROM AUTHOR]