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In recent years, related research has mainly examined lipophilic marine toxins (LMTs) in contaminated bivalves or toxic algae, whereas the levels of LMTs in seawater remain largely unexplored. Okadaic acid (OA), yessotoxin (YTX), and pectenotoxin-2 (PTX2) are three typical LMTs produced by certain marine algae that are closely linked to diarrhetic shellfish poisoning. In this study, a new method of solid phase extraction combined with liquid chromatography - electrospray ionization ion trap tandem mass spectrometry was developed to determine the presence of OA, YTX, and PTX2 in seawater simultaneously. Satisfactory sensitivity, repeatability (RSD < 25.00%) and recovery (56.25-70.18%) of the method were achieved. Then, the method was applied to determine the amounts of the three toxins in the coastal seawater. OA and PTX2 were detected in all the seawater samples collected from eight locations along the coastline of Qingdao City, China on October 23, 2012, with concentration ranges of OA 4.24-9.64 ng L-1 and PTX2 0.42-0.74 ng L-1. Monthly concentrations of OA and PTX2 in the seawater of four locations were determined over the course of a year, with concentration ranges of OA 1.41-89.52 ng L-1 and PTX2 below detectable limit to 1.70 ng L-1. The peak values of OA and PTX2 in coastal seawater were observed in August and July, respectively. Our results suggest that follow-up research on the fate modeling and risk assessment of LMTs in coastal seawater should be implemented. [ABSTRACT FROM AUTHOR]

Abstract: Zinc (Zn) and silver (Ag) are co-implanted into titanium by plasma immersion ion implantation. A Zn containing film with Ag nanoparticles (Ag NPs) possessing a wide size distribution is formed on the surface and the corrosion resistance is improved due to the micro-galvanic couples formed by the implanted Zn and Ag. Not only are the initial adhesion, spreading, proliferation and osteogenic differentiation of rBMSCs observed from the Zn/Ag implanted Ti in vitro, but also bacteria killing is achieved both in vitro and in vivo. Electrochemical polarization and ion release measurements suggest that the excellent osteogenic activity and antibacterial ability of the Zn/Ag co-implanted titanium are related to the synergistic effect resulting from the long-range interactions of the released Zn ions and short-range interactions of the embedded Ag NPs. The Zn/Ag co-implanted titanium offers both excellent osteogenic activity and antibacterial ability and has large potential in orthopedic and dental implants. [Copyright &y& Elsevier]

Insulin and adrenergic stimulation are two divergent regulatory systems that may interact under certain pathophysiological circumstances. Here, we characterized a complex consisting of insulin receptor (IR) and β2- adrenergic receptor (β2AR) in the heart. The IR/β2AR complex undergoes dynamic dissociation under diverse conditions such as Langendorff perfusions of hearts with insulin or after euglycemic-hyperinsulinemic clamps in vivo. Activation of IR with insulin induces protein kinase A (PKA) and G-protein receptor kinase 2 (GRK2) phosphorylation of the β2AR, which promotes β2AR coupling to the inhibitory G-protein, Gi. The insulin-induced phosphorylation of β2AR is dependent on IRS1 and IRS2. After insulin pretreatment, the activated β2AR-Gi signaling effectively attenuates cAMP/PKA activity after β-adrenergic stimulation in cardiomyocytes and consequently inhibits PKA phosphorylation of phospholamban and contractile responses in myocytes in vitro and in Langendorff perfused hearts. These data indicate that increased IR signaling, as occurs in hyperinsulinemic states, may directly impair βAR-regulated cardiac contractility. This β2AR-dependent IR and βAR signaling cross-talk offers a molecular basis for the broad interaction between these signaling cascades in the heart and other tissues or organs that may contribute to the pathophysiology of metabolic and cardiovascular dysfunction in insulin-resistant states. [ABSTRACT FROM AUTHOR]

Small-molecule, ligand-activated G protein-coupled receptors are generally thought to be rapidly desensitized within a period of minutes through receptor phosphorylation and internalization after repeated or prolonged stimulation. This transient G protein-coupled receptor activation remains at odds with many observed long-lasting cellular and physiological responses. Here, using live cell imaging of cAMP with a FRET-based biosensor and myocyte contraction assay, we show that the catecholamine-activated β1 adrenergic receptor (β1AR) continuously stimulates second messenger cAMP synthesis in primary cardiac myocytes and neurons, which lasts for more than 8 h (a decay Uh of 3.9 h) in cardiac myocytes. However, the β1AR-induced cAMP signal is counterbalanced and masked by the receptor-bound phosphodiesterase (PDE) 4D8-dependent cAMP hydrolysis. Inhibition of PDE4 activity recovers the receptor-induced cAMP signal and promotes contractile response in mouse hearts during extended periods of agonist stimulation. β1AR associates with PDE4D8 through the receptor C-terminal PDZ motif-dependent binding to synaptic-asso-ciated protein 97 (SAP97). Knockdown of SAP97 or mutation of the β1AR PDZ motif disrupts the complex and promotes sustained agonist-induced cAMP activity, PKA phosphorylation, and cardiac myocyte contraction response. Together, these findings unveil a long lasting adrenergic signal in neurons and myocytes under prolonged stimulation and an underappreciated role of PDE that is essential in classic receptor signaling desensitization and in maintaining a long lasting cAMP equilibrium for ligand-induced physiological response. [ABSTRACT FROM AUTHOR]

Zirconia films were prepared on titanium by cathodic arc deposition technique. The surface topography and element composition of the films were characterized by scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. Osteoblast-like MG63 cells were cultured on the surface of the zirconia films in vitro, and cell behaviour was investigated, with titanium as control. The results obtained from scanning electron microscopy and immunofluorescence studies showed that the MG63 cells on ZrO2 films spread better than those on Ti. The CCK8 assay indicated that the zirconia films promoted the proliferation of MG63 cells. The results of alkaline phosphatase (ALP) activity test and the expression of osteogenic marker genes, such as ALP, collagen I and osteocalcin, demonstrated that the differentiation of MG63 cells might be enhanced by zirconia films. In addition, the zirconia films possibly regulated osteoclastogenic gene expression by stimulating the expression of osteoprotegerin and reducing the expression of receptor activator of nuclear factor-kappaB ligand. The present work suggests that the ZrO2 film is worth further consideration for orthopedic implant applications. [ABSTRACT FROM AUTHOR]

Herein, a novel smart chemical strategy for regulating the corrosion reaction to reinforce the plasma electrolytic oxidation (PEO) coating on magnesium by amorphous MnOOH is proposed. The MnOOH film could provide PEO coating with both physical shielding and chemical active healing abilities. During corrosion process, MnOOH spontaneously reacts with the corrosion-produced Mg2+ and OH– to form layered double hydroxides, resulting in high improvement of the long-term anti-corrosion of PEO coating. Moreover, the PEO/MnOOH coating presented a certain self-healing ability for scratches, and could be used for repairing corrosion defects on further coated films. [Display omitted] • An amorphous MnOOH film was prepared on PEO coating via a facile immersion treatment. • MnOOH film could react with corrosion produced Mg2+ and OH- to form protective LDH. • MnOOH film could cut-off the vicious cycle in corrosion reactions of PEO coating. • PEO/MnOOH coating had a certain self-healing ability for scratch and coated films. [ABSTRACT FROM AUTHOR]

Alzheimer disease (AD) is characterized by neurodegeneration marked by loss of synapses and spines associated with hyperphosphorylation of tau protein. Accumulating amyloid β peptide (Aβ) in brain is linked to neurofibrillary tangles composed of hyperphosphorylated tau in AD. Here, we identify β2-adrenergic receptor β2AR) that mediates Aβ-induced tau pathology. In the prefrontal cortex (PFC) of 1-year-old transgenic mice with human familial mutant genes of presenilin 1 and amyloid precursor protein (PS1/APP), the phosphorylation of tau at Ser-214 Ser-262 and Thr-181, and the protein kinases including JNK, GSK3α/β, and Ca2+/calmodulin-dependent protein kinase II is increased significantly. Deletion of theβ2AR gene in PS1/APP mice greatly decreases the phosphorylation of these proteins. Further analysis reveals that in primaryPFCneurons, Aβ signals through a β2AR-PKA-JNK pathway, which is responsible for most of the phosphorylation of tau at Ser-214 and Ser-262 and a significant portion of phosphorylation at Thr- 181. Aβ also induces a β2AR-dependent arrestin-ERK1/2 activity that does not participate in phosphorylation of tau. However, inhibition of the activity of MEK, an upstream enzyme of ERK1/2, partially blocks Aβ-induced tau phosphorylation at Thr-181. The density of dendritic spines and synapses is decreased in the deep layer of the PFC of 1-year-old PS1/APP mice, and the mice exhibit impairment of learning and memory in a novel object recognition paradigm. Deletion of the β2AR gene ameliorates pathological effects in these senile PS1/APP mice. The study indicates that β2AR may represent a potential therapeutic target for preventing the development of AD. [ABSTRACT FROM AUTHOR]

Two new compounds, 5β-pregnane-2α,6α,20(S)-triol (1) and 8-hydroxyl-3-methoxyl-2(1H)-quinolone (2), were isolated fromScolopendra multidensNewport. Their structures were elucidated on the basis of spectroscopic methods including 1D and 2D NMR and HR-TOF-MS. [ABSTRACT FROM PUBLISHER]

Tylophorine analogs exhibit a broad range of pharmacological activities, including anti-cancer, anti-inflammatory, antiautoimmune, and anti-virus effects. Structure-activity relationship study of different structure tylophorine analogs can provide further understanding of their biological activity. Modifications on the E ring of the quinolizidine moiety of cryptopleurine analogs changed the potency and the selective inhibitory effect on NF-κB, AP-1, and CRE signaling pathways. Functional cryptopleurine analogs showed potent inhibition of NF-κB signaling pathway in both HepG2 and HEK- 293 cell lines. The E ring structure analogs also differed in suppression of protein translation, and expression of cyclin D1. Our results showed that DCB-3503 or Rac-cryptopleurine could be a scaffold for modification to yield compounds with different mechanisms of action. [ABSTRACT FROM AUTHOR]

During meiotic recombination, induced double-strand breaks (DSBs) are processed into crossovers (COs) and non-COs (NCO); the former are required for proper chromosome segregation and fertility. DNA synthesis is essential in current models of meiotic recombination pathways and includes only leading strand DNA synthesis, but few genes crucial for DNA synthesis have been tested genetically for their functions in meiosis. Furthermore, lagging strand synthesis has been assumed to be unnecessary. Here we show that the Arabidopsis thaliana DNA REPLICATION FACTOR C1 (RFC1) important for lagging strand synthesis is necessary for fertility, meiotic bivalent formation, and homolog segregation. Loss of meiotic RFC1 function caused abnormal meiotic chromosome association and other cytological defects; genetic analyses with other meiotic mutations indicate that RFC1 acts in the MSH4-dependent interference-sensitive pathway for CO formation. In a rfc1 mutant, residual pollen viability is MUS81-dependent and COs exhibit essentially no interference, indicating that these COs form via the MUS81-dependent interference-insensitive pathway. We hypothesize that lagging strand DNA synthesis is important for the formation of double Holliday junctions, but not alternative recombination intermediates. That RFC1 is found in divergent eukaryotes suggests a previously unrecognized and highly conserved role for DNA synthesis in discriminating between recombination pathways. [ABSTRACT FROM AUTHOR]

Inflammation is a significant player in the progression of heart failure and has detrimental effects on cardiac function. Prostaglandin (PG)E2, a major proinflammatory prostanoid in the cardiovascular system, is a potent stimulus in inducing intracellular CAMP but minimally affects cardiac contractile function. Here, we show that the PGE2 stimulation attenuates the adrenergic-induced cardiac coiitractile response in animal hearts. Stimulation with PGE2 leads to stimulatory G protein (Gs)-dependent production of CAMP. However, the induced CAMP is spatially restricted because of its degradation by phosphodiesterase (PDE)4 and cannot access the intracellular sarcoplasmic reticulum (SR) for increasing calcium signaling and myocyte contraction. Moreover, pretreatment with PGE2 significantly inhibits PKA activities at the SR induced by a β-adrenergic agonist, isoproterenol, and subsequently blocks isoproterenol-induced PKA phosphorylation of phospholamban and contractile responses in myocytes. Further analysis reveals that the PGE2-induced cAMP/PKA is sufficient to phosphorylate and activate PDE4D isoforms, which, in turn, spatially inhibits the diffusion of adrenergic-induced CAMP from the plasma membrane to the SR. Inhibition of PDE4 rescues the adrenergic-induced increase in cAMP/PKA activities at the SR. PKA phosphorylation of phospholamban, and contractile responses in PGE2-pretreated myocytes. Thus, this offers an example that one Gs-coupled receptor is able to inhibit the intracellular signaling transduction initiated by another Gs-coupled receptor via controlling the diffusion of CAMP, presenting a paradigm for G protein-coupled receptor (GPCR) signal transduction. It also provides a mechanism for the integration of signaling initiated by different neurohormonal stimuli, as well as long-term effects of chronically circulating proinflammatory factors in myocardium. [ABSTRACT FROM AUTHOR]

Background: Natural killer (NK) cells activation has been reported to contribute to inflammation and liver injury during hepatitis B virus (HBV) infection both in transgenic mice and in patients. However, the role of NK cells in the process of HBV-associated hepatocellular carcinoma (HCC) development has not been addressed. Killer cell immunoglobulin-like receptors (KIRs) are involved in regulating NK cell activation through recognition of specific human leukocyte antigen (HLA) class I allotypes. Methodology/Principal Findings: To investigate whether KIR and HLA genes could influence the risk of HBV-associated HCC development, 144 HBV-infected patients with HCC and 189 well-matched HBV infectors with chronic hepatitis or cirrhosis as non-HCC controls were enrolled in this study. The presence of 12 loci of KIR was detected individually. HLA-A, -B, -C loci were genotyped with high-resolution. HLA-C group 1 homozygote (OR = 2.02; p=0.005), HLA-Bw4-80I (OR = 2.67; p=2.0E-04) and combination of full-length form and 22 bp-deleted form of KIR2DS4 (KIR2DS4/1D) (OR = 1.89; p=0.017) were found associated with HCC incidence. When the combined effects of these three genetic factors were evaluated, more risk factors were observed correlating with higher odds ratios for HCC incidence (P trend = 7.4E-05). Because all the risk factors we found have been reported to result in high NK cell functional potential by previous studies, our observations suggest that NK cell activation may contribute to HBV-associated HCC development. Conclusions/Significance: In conclusion, this study has identified significant associations that suggest an important role for NK cells in HCC incidence in HBV-infected patients. Our study is useful for HCC surveillance and has implications for novel personalized therapy strategy development aiming at HCC prevention in HBV-infected patients. [ABSTRACT FROM AUTHOR]

Background: Porcine parvovirus (PPV) VP2 gene has been successfully expressed in many expression systems resulting in self-assembly of virus-like particles (VLPs) with similar morphology to the native capsid. Here, a pseudorabies virus (PRV) system was adopted to express the PPV VP2 gene. Methods: A recombinant PRV SA215/VP2 was obtained by homologous recombination between the vector PRV viral DNA and a transfer plasmid. Then recombinant virus was purified with plaque purification, and its identity confirmed by PCR amplification, Western blot and indirect immunofluorescence (IFA) analyses. Electronic microscopy of PRV SA215/VP2 confirmed self-assembly of both pseudorabies virus and VLPs from VP2 protein. Results: Immunization of piglets with recombinant virus elicited PRV-specific and PPV-specific humoral immune responses and provided complete protection against a lethal dose of PRV challenges. Gilts immunized with recombinant viruses induced PPV-specific antibodies, and significantly reduced the mortality rate of (1 of 28) following virulent PPV challenge compared with the control (7 of 31). Furthermore, PPV virus DNA was not detected in the fetuses of recombinant virus immunized gilts. Conclusions: In this study, a recombinant PRV SA215/VP2 virus expressing PPV VP2 protein was constructed using PRV SA215 vector. The safety, immunogenicity, and protective efficacy of the recombinant virus were demonstrated in piglets and primiparous gilts. This recombinant PRV SA215/VP2 represents a suitable candidate for the development of a bivalent vaccine against both PRV and PPV infection. [ABSTRACT FROM AUTHOR]

The purpose of this study was to develop a new prognostic scoring system for critically ill patients using the simple complete blood cell count (CBC).~Objective~Objective~CBC measurements in samples from 306 patients in an intensive care unit were conducted with automated analyzers, including levels of neutrophils, lymphocytes, erythrocytes, hemoglobin, and platelets. The time of sampling and the time of death were recorded. Z values were calculated according to the measured values, reference mean values, and standard deviations. The prognostic score was equivalent to the median of the Z value of each of the measured parameters.~Methods~Methods~There was a significant correlation between survival time and neutrophil, lymphocyte, and platelet levels (P < 0.05). Prognostic scores were calculated from the Z value of these three parameters. Survival times decreased as the prognostic score increased.~Results~Results~This study suggests that a model that uses levels of neutrophils, lymphocytes, and platelets is potentially useful in the objective evaluation of survival time or disease severity in unselected critically ill patients.~Conclusions~Conclusions [ABSTRACT FROM AUTHOR]

Abstract: A white-rot fungus, strain SQ01, was isolated from decayed wood in a temperate forest. The strain was identified as a member of genus Trametes, based on the morphological characteristics and a complete sequence analysis of its 18S rRNA gene and ITS region. Strain SQ01 was capable of decolorizing a variety of synthetic dyes, including azo, triphenylmethane, and anthraquinone dyes, with an optimal efficiency of decolorization obtained when dyes added after 5 days of culture, with the exception of Cresol Red, showing that the point of dye addition was an important influencing factor for decolorization by this fungus. All of the tested dyes were decolorized by the purified laccase in the absence of any redox mediators, but only a few were completely removed, while others were not completely degraded even with increased decolorization time. [Copyright &y& Elsevier]

Abstract: Copper nanoparticles embedded in soda-lime glass were fabricated by ion exchange followed by thermal treatment in hydrogen. The ultrafast dynamics of the embedded Cu nanoparticles formed under different fabrication conditions were investigated by applying femtosecond pump-probe technique. Non-Fermi electrons were suggested to be dominant in the transient behavior of the nanocomposites far from surface plasmon resonance of Cu. The long ion-exchange processing time was found to benefit and improve the ultrafast response of the fabricated nanocomposites. [Copyright &y& Elsevier]

Abstract: Effects of thermal treatment on the third-order optical nonlinearity and ultrafast dynamics of Ag nanoparticles embedded in glasses were investigated by femtosecond time-resolved OKE and femtosecond pump–probe techniques. The results indicate that the third-order susceptibility increases from 1.1×10−11 esu to 1.48×10−9 esu with increasing the annealing temperature. The fast decay process is accelerated and its amplitude ratio increases with the thermal treatment, which could be attributed to an increase of the electron–phonon coupling through the process of treelike Ag nanoparticle aggregation. The slow relaxation time ranges from 25ps to 140ps, depending on the thermal conductivity of the matrix material. [Copyright &y& Elsevier]

Tylophorine and related natural compounds exhibit potent antitumor activities. We previously showed that PBT-1, a synthetic C9-substituted phenanthrene-based tylophorine (PBT) derivative, significantly inhibits growth of various cancer cells. In this study, we further explored the mechanisms and potential of PBT-1 as an anticancer agent. PBT-1 dose-dependently suppressed colony formation and induced cell cycle G2/M arrest and apoptosis. DNA microarray and pathway analysis showed that PBT-1 activated the apoptosis pathway and mitogen-activated protein kinase signaling. In contrast, PBT-1 suppressed the nuclear factor kappaB (NF-κB) pathway and focal adhesion. We further confirmed that PBT-1 suppressed Akt activation accelerated RelA degradation via IκB kinase-α and down-regulated NF-κB target gene expression. The reciprocal recruitment of RelA and RelB on COX-2 promoter region led to down-regulation of transcriptional activity. We conclude that PBT-1 induces cell cycle G2/M arrest and apoptosis by inactivating Akt and by inhibiting the NF-κB signaling pathway. PBT-1 may be a good drug candidate for anticancer chemotherapy. [ABSTRACT FROM AUTHOR]

Glycerol dialkyl glycerol tetraethers (GDGTs) are widespread but unique membrane-spanning lipids of many Archaea and some Bacteria. However, their specific biological sources and the associated environmental controls on their distribution remain unclear, especially in lacustrine settings, hindering our understanding of these compounds and their application as environmental proxies. Here we investigated the GDGT distributions across a large bottom water dissolved oxygen (DO) gradient (0.10–7.20 mg/L) using surface sediments of Lake Yangzonghai, a warm monomictic lake in southwestern China. We show that the distributions of both branched (br) and isoprenoidal (iso) GDGTs co-vary significantly with bottom water DO concentration. The relative abundances of tetramethylated brGDGTs, 5-methyl penta- and hexamethylated brGDGTs and isoGDGT-0 show a stepwise increase as bottom water DO concentration decreases. On the other hand, the relative abundances of 6-methyl penta- and hexamethylated brGDGTs and crenarchaeol exhibit a stepwise decline with a decrease in bottom water DO concentration. Genetic data indicate these DO-induced changes in GDGT parameters are related to changes in the bacterial and archaeal communities across the oxycline in the lake. For example, the high abundance of isoGDGT-0 in low DO samples coincides with a high abundance of methanogenic archaea and Bathyarchaeota. We propose that brGDGT-producing bacteria might include a diversity of other phyla in addition to the proposed source organism acidobacteria; different groups of anaerobic and aerobic bacteria are likely to contribute to the increased abundance of 5-methyl brGDGTs and 6-methyl brGDGTs in low and high DO zones, respectively. Consequently, the MBT′ and MBT′ 6ME brGDGT indices display strong correlations with DO concentration. Importantly, the MBT′ 5ME index is not significantly influenced by changes in DO concentration, suggesting that this index might be more resilient to these impacts and more suitable to reconstruct temperature in lake systems. • One of the most systematic investigation on DO impact on all the GDGT compounds and the related paleoclimate proxies • A new ternary diagram was used to identity the sources of lacustrine brGDGTs • Anaerobic and aerobic bacteria contribute to the increased abundance of 5-methyl and 6-methyl brGDGTs, respectively • MBT′ 5ME might be more suitable to reconstruct temperature in lake systems than MBT′ and MBT′ 6ME [ABSTRACT FROM AUTHOR]

The largemouth bass (Micropterus salmoides) is an economically important fish species, but disease caused by Aeromonas hydrophila has led to the high mortality of this fish in farming environments. However, few studies have focused on the differences in the responses of largemouth bass to infection and immunization with A. hydrophila. In the present study, we found high fish mortality after A. hydrophila infection but not after immunization. Then, the immune response difference of largemouth bass in early infection and immunization with A. hydrophila was analyzed using transcriptome profiling and 16S rRNA sequencing. The results from the transcriptome analysis revealed that many upregulated genes were enriched in metabolic pathways after infection and immunization, but the number of upregulated genes associated with metabolic pathways and the magnitude of their upregulated expression in the infection group were much greater than they were in the immunization group, suggesting that A. hydrophila infection might cause metabolic disorders in largemouth bass. Increases in pro-inflammatory cytokine levels and reduced expression of genes associated with adaptive immunity were also observed in the infection group. Moreover, the results of the 16S rRNA analysis revealed that the intestinal microbiota homeostasis of the largemouth bass was severely disrupted by A. hydrophila infection but not by immunization. These results collectively demonstrated that metabolic disorders, higher inflammation, a reduced adaptive immune response and disrupted microbiota homeostasis in early infection might be important factors for the high mortality of largemouth bass caused by A. hydrophila infection. • High mortality of largemouth bass after A. hydrophila infection, but not after immunization. • Metabolic disorders in largemouth bass were found in early stages of infection. • Higher inflammation and lower adaptive immune response in largemouth bass were found in early stages of infection. • Disrupted microbiota homeostasis in largemouth bass were found in early stages of infection. [ABSTRACT FROM AUTHOR]

Two new two-photon absorption (TPA) molecules, named SK-G1 and NT-G1, are synthesized and the photo-physical characteristics are investigated by using linear absorption spectra, one-photon fluorescence spectra and two-photon excited fluorescence spectra. Both the compounds exhibit TPA properties, and the TPA values determined by z-scan measurement are 10GMand 39GMfor SK-G1 and NT-G1, respectively, at wavelength 800nm. Time-resolved spectroscopic techniques are employed to further explore the excited state dynamics of NT-G1with larger TPA cross section. The research results show that there is an ultrafast intraband energy transfer process (about 3ps) before the formation of charge transfer state with a relatively long lifetime. [ABSTRACT FROM AUTHOR]

Two soluble polymer grafted multi-walled carbon nanotubes (MWNTs), including poly(N-vinylcarbazole)-MWNTs and poly(methyl methacrylate)-MWNTs, are synthesized. Their nonlinear optical properties and optical limiting (OL) performances are investigated by z-scan method with 527nm nanosecond laser pulses. These grafted MWNTs dissolved in chloroform show much better optical limiting performance than those of MWNTs and C60 in toluene solution. Nonlinear absorption and nonlinear scattering mechanism are taken into consideration for explaining the observed results. The comparison of the experimental results shows that nonlinear absorption is the dominant mechanism for OL performance of these new samples. [ABSTRACT FROM AUTHOR]

Abstract: Multiwalled carbon nanotube (MWCNT)/polystyrene (PS) or poly(methyl methacrylate) (PMMA) composites were successfully prepared by in situ emulsion polymerization under microwave irradiation using potassium persulfate as initiator. Then the composites were treated with tetrahydrofuran (THF) to remove the free polymers. The resultant PS or PMMA-wrapped MWCNT samples, which were soluble in common organic solvents such as 1,2-dichlorobenzene, THF, chloroform and others, have been well-characterized by TEM, thermal gravimetric analyses, FT-IR, UV–vis and Raman spectra. The optical limiting properties of the polymer-wrapped MWCNT samples were investigated by open-aperture z-scan method. All of the polymer modified MWCNT samples in chloroform showed much better optical limiting behavior than pristine MWCNT in chloroform. [Copyright &y& Elsevier]

Abstract: In order to improve the laccase activity, mutant libraries are constructed through ethyl methane sulfonate-based (EMS) random mutagenesis. Mutagenesis improved expression 3.7-fold to 144mgl−1 laccase in yeast, together with a 1.4-fold increase in K cat. Thus, the total activity is enhanced 5-fold for 2,2′-azino-bis 3-ethylbenzothiaoline-6-sulfonic acid (ABTS). In the presence of 0.6mM copper, the highest activity value reached 30Uml−1 after a 3-day cultivation at a temperature of 30°C. In comparison with the wild type, the best mutant enzymatic properties (K m for ABTS and guaiacol, thermo- and pH stability, optimal pH) are not changed. Moreover, amino acid sequence analysis indicates that there are four substitutions in the best mutant laccase (Gly160Asp, Ala167Thr, Gly174Asp, and Glu234Gly). The best mutant laccase model showed that the Gly160 and Ala167 are to be found near the water channel; especially the distance of Ala167 to the Cu3a is 14.46Å. This implies that it is likely involved in the formation of water channel and that it helps facilitate the easy incoming and outgoing of water. [Copyright &y& Elsevier]

Abstract  Co-crystallization of melamine(MA) and sulfate results in crystalline product [(C3H7N6)2(SO42−)] � 2H2O. The novel supramolecular complex has been characterized by elemental analysis, thermal analysis (TGA and DSC), nuclear magnetic resonance (NMR), and single crystal X-ray diffraction. X-ray crystallographic studies of the complex reveal that the title complex has a 3-D microporous structure which is linked by intense intermolecular hydrogen-bonding interactions (N–H������O, N–H������N, O–H������O) and aromatic π-π interaction, which stabilize the whole crystal framework. The TGA curve shows that the complex is stable up to 500 �C, above which its structure begins to collapse. [ABSTRACT FROM AUTHOR]

Abstract: We studied the photoluminescence (PL) properties of self-organized para-sexiphenyl (PSP) nano-needles with linear and nonlinear optical excitation. Excited by femtosecond pulses, two-photon absorption (TPA) induced PL emission peaks corresponding to the vibronic transitions in PSP molecules were observed. Polarization-dependent photoluminescence measurements reveal that the TPA induced PL in the highly-ordered structures, similar with the linear excitation case, is strongly dependent on the excitation polarization. The mechanism that the nonlinear transition dipole moment is oriented parallel to the long axis of the molecular for the π–π∗ absorption in PSP is suggested to explain these strong polarization effects. [Copyright &y& Elsevier]

Abstract: Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin (NHFS) was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No.16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein (KU: keratinase unit). Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40°C to 55°C. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development. [Copyright &y& Elsevier]

Abstract: A novel quantitative real-time PCR method using the duplex scorpion primer for detection of Chlamydia trachomatis DNA was developed and validated. The assay employs a duplex primer; its most important feature is the intramolecular probe–target interaction. The assay had many prominent characteristics. (i) The duplex probe is simpler to synthesize and significantly easier to purify than TaqMan probe because that the fluorescent dye pair and the quencher pair are in different oligonucleotides. (ii) The method has high sensitivity, specificity, intra- and interassay reproducibilities. (iii) The assay has a quantitative dynamic range of 25 to109 genome copies per reaction mixture. (iv) The scorpion system can identify 98.6% samples in the validation panel without retest. There were 81 positive samples and 67 negative samples, which were confirmed by two FDA-approved NAATs (the Roche Amplicor PCR assay, Abbott LCR kit) and our new method. Any two positive results out of the possible three-comparator results would define the infected-patient gold standard. Of the positive samples, 79 (97.5%) were found positive (ranging from 31 to 227,648 copies/μl, M =4219 copies/μl), whereas no negative samples were found positive by the assay. A quantitative, fast, and easy-to-handle diagnostic approach such as the MOMP-based real-time PCR described here might improve the detection of C. trachomatis infection. [Copyright &y& Elsevier]

Abstract: In this work, samples of poly(N-vinyl carbazole) (PVK)-grafted multiwalled carbon nanotubes (MWCNTs) were synthesized via free radical reaction. The ready-made PVK was allowed to react directly with MWCNTs at 70°C in the presence of azo-bis-isobutyronitrile (AIBN). The purified deep grey products, which can dissolve in common organic solvents such as chloroform and 1,2-dichlorobenzene (DCB), were then characterized by FTIR spectra, TEM, TGA, elemental analysis, XPS, UV–vis spectra and Raman spectra. It was confirmed that PVK chains were grafted onto the surface of the carbon nanotubes (CNTs). The optical limiting properties of these PVK-grafted MWCNTs samples were investigated by open-aperture z-scan method. All of the samples of PVK-modified carbon nanotubes in chloroform showed optical limiting behavior better than that of C60 in toluene. [Copyright &y& Elsevier]

Ultrafast third-order optical nonlinearities of the as-deposited and annealed Au:Bi2O3 nanocomposite films deposited by magnetron cosputtering are investigated by using femtosecond time-resolved optical Kerr effect (OKE) and pump-probe techniques. The third-order optical nonlinear susceptibility is estimated to be 2.6x10[?]10 esu and 1.8x10[?]9 esu at wavelength of 800 nm, for the as-deposited and the annealed film, respectively. The OKE signal of the as-deposited film is nearly temporally symmetrical with a peak centred at zero delay time, which indicates the dominant contribution from intraband transition of conduction electrons. For the annealed film, the existence of a decay process in OKE signal implies the important contribution of hot electrons. These characteristics are in agreement with the hot electron dynamics observed in pump-probe measurement. [ABSTRACT FROM AUTHOR]

Abstract: Since transglutaminase (TGase) have been widely used in industry, mass production of the enzyme is especially necessary. The mature TGase gene from Streptomyces fradiae was cloned into pET21a and overexpressed in Escherichia coli BL21(DE3). The recombinant TGase was formed as inclusion bodies, and its content was as high as 55% of the total protein content. The insoluble fractions were separated from cellular debris by centrifugation and solubilized with 8M urea. With an on-column refolding procedure based on cation SP Fast Flow chromatography with dual-gradient, the active TGase protein was recovered efficiently from inclusion bodies. The final purified product was 95% pure detected by SDS–PAGE. Under appropriate experimental conditions, the protein yield and specific activity of the TGase were up to 53% and 21U/mg, respectively. Furthermore, the refolded recombinant protein demonstrated nearly identical ability to polymerized BSA compared with that of native TGase. One hundred and five milligrams of refolded TGase protein was obtained from 3.2g wet weight cells in the 400ml cell culture. [Copyright &y& Elsevier]

Background: Surgical repair of obstructive lesions of the right ventricular outflow tract (RVOT) commonly creates pulmonary valve incompetence, which continues to stimulate research for the optimal materials and surgical techniques to reconstruct RVOT. In this study, we present the early results with simultaneous enlargement of the pulmonary annulus and the pulmonary cusp with a transannular patch of autologous pericardium in RVOT reconstruction. Patients and methods: From January 2003 to December 2005, the surgical technique of simultaneous enlargement of the pulmonary annulus and the pulmonary cusp was used in 32 patients who had complex congenital heart anomalies with pulmonary artery hypoplasia. The functional status of the patients was followed up in the cardiologic clinic of our institute. The motion of the newly constructed valve and the degree of pulmonary insufficiency were evaluated by echocardiography before discharge and at 2–6 months, 12 months, and 36 months postoperatively. Results: Early death occurred in one patient (3.1%). Postoperative complications occurred in six patients but they recovered uneventfully. During the follow-up, 28 of 31 operative survivors were in New York Heart Association functional class I without medication and the other three were in class II. Seventeen patients had no or trivial pulmonary regurgitation; mild regurgitation was present in 12 patients, and moderate regurgitation was seen in 2 patients. None of these patients needed reoperation and echocardiography showed good motion of the reconstructed valve. Conclusions: The surgical technique of simultaneous enlargement of the pulmonary annulus and the pulmonary cusp with a transannular patch of autologous pericardium is a safe, reliable, and effective way for RVOT reconstruction. Satisfactory early results have been achieved; however, long-term follow-up is necessary to determine the true value of this technique. [Copyright &y& Elsevier]

Abstract: The energy relaxation dynamics in Ag:Bi2O3 nanocomposite films with high density of Ag nanoparticles were investigated by femtosecond pump–probe technique. For the films with relatively low Ag concentration (13.2–35.7at.%), the energy relaxation is nearly completed within 1picosecond (ps) at moderate excitation regime. For the film with 52.0at.% Ag concentration, the relaxation process consists of a fast power-dependent component (1–2ps) and a long-lived one. The different relaxation characteristics are suggested to be resulted from the differences in the structural and thermal properties of the surrounding Bi2O3 matrix coupling with Ag nanoparticles. [Copyright &y& Elsevier]

Abstract: Femtosecond degenerate pump–probe spectroscopy was carried out on thin films of a series of axially substituted phthalocyanines including tBu4PcInCl(tBu4=tetra-(tert-butyl)), tBu4PcTiO, tBu4PcIn(p-TMP) [p-TMP=p-trifluoromethylphenyl], tBu4PcGa(p-CPO) [p-CPO=p-chlorophenoxy], and μ-oxo-bridged phthalocyanine dimers, e.g., [tBu4PcIn]2O, tBu4PcIn–O–GaPctBu4 and [tBu4PcGa]2O. We demonstrate that the long lived state of the dynamics is the triplet state and the behavior of the degenerate pump–probe was determined by exciton–exciton annihilation (E-EA), nonradiative recombination (NR) and intersystem crossing (ISC) processes. The E-EA process is via the long-range dipole–dipole interaction between excitons or motion-limited diffuse other than exciton hopping migrations. The dimers shows much efficient E-EA and the indium-contained samples have larger ISC rate than the others. [Copyright &y& Elsevier]

Two new hyperbranched phenylene vinylenes (HPVs) with triphenylamine as the core, 2,5-dihexyloxyl substituted phenylene vinylene as the connecting unit, and electron-donating triphenylamine or electron-deficient nitrobenzene as the different terminal groups were synthesized by modified Wittig polymerization reaction. Their one- and two-photon absorption (TPA) properties have been investigated. The two-photon absorption cross sections of the two polymers were performed by open-aperture Z-scan experiment using 120 femtosecond (fs) pulse, and their TPA cross section were determined to be 1.43 and 0.64×10-20cm4/GW per repeating unit at 800nm, respectively. In chloroform, HPVs exhibit intense frequency up-converted fluorescence under the excitation of 120fs pulses at 800nm with the peaks located at 544 and 554nm, respectively. [Copyright &y& Elsevier]

Studies novel silver-containing supramolecular frameworks constructed by combination of coordination bonds and supramolecular interactions. Hydrothermal reactions of AgNO[sub 3] and carboxylate ligands; Generation of three-dimensional supramolecular structure by ag-O interactions.

Examines the synthesis of three-dimensional channel-like polymeric lanthanide complexes by 1,2,45-Benzenetetracarboxylic acid. Creation of inorganic coordination polymeric complexes; Ability to form hydrogen bonds; Evaluation on thermal gravimetric analysis on Delta Series TGA seven instrument.

The connexin (Cx) 50, E48K, mutation is associated with a human dominant congenital cataract; however, the underlying molecular mechanism has not been characterized. The glutamate (E) residue at position 48 is highly conserved across animal species and types of connexins. When expressed in paired Xenopus oocytes, human (h) and chicken (ch) Cx50 E48K mutants showed no electrical coupling. In addition, this mutation acts in a dominant negative manner when paired hetero-typically or hetero-merically with wild-type Cx50, but has no such effect on Cx46, the other lens fiber connexin. A similar loss-of-function and dominant negative effect was observed using dye transfer assays in the same system. By using two different dye transfer methods, with two different tracer dyes, we found chCx50 E48K expressed in chicken lens embryonic fibroblast cells by retroviral infection similarly failed to induce dye coupling, and prevented wild-type chCx50 from forming functional gap junctions. In contrast to its effect on gap junctions, the E48K mutation has no effect on hemichannel activity when assayed using electrical conductance in oocytes, and mechanically induced dye uptake in cells. Cx50 is functionally involved in cell differentiation and lens development, and the E48K mutant promotes primary lens cell differentiation indistinguishable from wild-type chCx50, despite its lack of junctional channel function. Together the data show that mutations affecting gap junctions but not hemichannel function of Cx50 can lead to dominant congenital cataracts in humans. This clearly supports the model of intercellular coupling of fiber cells creating a microcirculation of nutrients and metabolites required for lens transparency. [ABSTRACT FROM AUTHOR]

We previously reported that, among the three connexins expressed in chick lens, overexpression of connexin (Cx) 45.6, not Cx43 or Cx56, stimulates lens cell differentiation; however, the underlying mechanism responsible for this effect is unclear. Here, we took advantage of naturally occurring loss-of-gap-junction function mutations of Cx50 (ortholog of chick Cx45.6) and generated the corresponding site mutants in Cx45.6: Cx45.6(D47A) and Cx45.6(P88S). In contrast to wild-type Cx45.6, the mutants failed to form functional gap junctions, and Cx45.6(P88S) and, to a lesser degree, Cx45.6(D47A) functioned in a dominant-negative manner. Interestingly, overexpression of both mutants incapable of forming gap junctions significantly increased epithelial-fiber differentiation to a level comparable to that of wild-type Cx45.6. To map the functional domain of Cx45.6, we generated a C-terminus chimera as well as deletion mutants. Overexpression of Cx56*45.6C, the mutant in which the C-terminus of Cx56 was replaced with that of Cx45.6, had a stimulatory effect on lens cell differentiation similar to that of Cx45.6. However, cells overexpressing Cx45.6*56C, the mutant in which C-terminus of Cx45.6 was replaced with that of Cx56, and Cx45.6( C), in which the C-terminus was deleted, failed to promote differentiation. Taken together, we conclude that the expression of Cx45.6, but not Cx45.6-dependent gap junction channels, is involved in lens epithelial-fiber cell differentiation, and the C-terminal domain of Cx45.6 plays a predominant role in mediating this process. [ABSTRACT FROM AUTHOR]

The title compound, C18H9Cl2F3N4O, is a tricyclic amide with an overall U-shaped molecule. [ABSTRACT FROM AUTHOR]

Chemical investigation on the aerial parts of Lycopus lucidus var. hirtus has afforded a novel abietane-type diterpenoid glycoside, lucihirtin A ( 1), and seven known compounds, ursolic acid 28-O- β-D-glucopyranoside ( 2), 2 α,3 β,19 α-trihydroxyurs-12-en-28-oic acid 28-O- β-D-glucopyranoside ( 3), 2 α,3 α,19 α-trihydroxyurs-12-en-28-oic acid ( 4), oleanolic acid ( 5), ursolic acid ( 6), palmitic acid ( 7), and 1-glycerin hexadecylate ( 8). Their structures and configurations were elucidated by spectroscopic methods, including 2D NMR techniques. Compounds 2, 3, 4, and 8 were isolated from this plant for the first time. [ABSTRACT FROM AUTHOR]

We reported a study of tunnel magnetoresistance (TMR) effect in single manganite nanowire via the combination of magnetotransport and magnetic force microscopy imaging. TMR value up to 290% has been observed in single (La1 − yPry)1 − xCaxMnO3 nanowires with varying width. We find that the TMR effect can be explained in the scenario of opening and blockade of conducting channels from inherent magnetic domain evolutions. Our findings provide a new route to fabricate TMR junctions and point towards future improvements in complex oxide-based TMR spintronics. [ABSTRACT FROM AUTHOR]

In polymeric {[Eu(pzdc)(NO3)(phen)(H2O)]·H2O}n [pzdc is 2,3-pyrazinedicarboxylate (C6H2O4) and phen is 1,10-phenanthroline (C12H8N2)], each europium(III) ion is coordinated by seven O atoms (from three pzdc anions, a nitrate anion and a water molecule) and the two N atoms of the phen ligand, resulting in a nine-coordinated europium(III) center with a distorted monocapped square-antiprismatic coordination polyhedron. Four pzdc anions bridge four europium(III) ions, forming a parallelogram unit, the four vertices of which are occupied by the four pzdc anions. Moreover, each parallelogram unit links six other adjacent parallelogram units, forming a two-dimensional network with disordered lattice water molecules. [ABSTRACT FROM AUTHOR]

An easily prepared and highly efficient monodentate phosphoramidite ligand derived from BINOL, (S)2,2'-O,O-(1,1'-binaphthyl)-dioxo-N,N-diethylphospholidine, was examined in the hydrogenation of both enamides and α-dehydroamino acid derivatives. The catalyst provided remarkably high enantioselectivities (up to 99.6% ee for enamides and >99.9% ee for α-dehydroamino acid derivatives). [ABSTRACT FROM AUTHOR]

Background: Natural killer (NK) cells play cytotoxic roles by targeting tumor cells or virus infected cells, they also play regulatory roles by secreting cytokines and chemokines. Transforming growth factor (TGF)-β and interleukin (IL)-10 are important immunosuppressive cytokines potentially related to the immune dysregulation that occurs in the infection of human immunodeficiency virus (HIV). NK cells are an important source of TGF-β and a main early producer of IL-10 in response to viral infection. Here, we evaluated the percentages of IL-10+ and TGF-β+ NK cells in HIV-infected patients relative to healthy controls (HCs).Methods: Study participants (n = 63) included 31 antiretroviral treatment (ART)-naïve HIV-infected patients, 17 ART-treated HIV-infected patients, and 15 HIV-negative HCs. Expression of IL-10 or TGF-β in NK cells was examined by flow cytometry, and the influences of recombinant IL-10 (rIL-10) or recombinant TGF-β (rTGF-β) on NK cell function were investigated in vitro.Results: Compared with HCs, ART-naïve HIV-infected patients had increased percentages of IL-10+ (2.0% vs. 0.4%, p = 0.015) and TGF-β+ (4.5% vs. 2.1%, p = 0.022) NK cells, and ART-treated patients also had a higher percentage of IL-10+ NK cells (2.5% vs. 0.4%, p = 0.002). The percentages of IL-10+ and TGF-β+ NK cells were positively correlated (r = 0.388; p = 0.010). The results of in vitro experiments demonstrated that rIL-10 and rTGF-β inhibited NK cell CD107a expression (p = 0.037 and p = 0.024, respectively), IFN-γ secretion (p = 0.006, p = 0.016, respectively), and granzyme B release after stimulation (p = 0.014, p = 0.040, respectively).Conclusions: Our data suggest that the percentages of IL-10+ or TGF-β+ NK cells are increased in HIV-infected patients, and that rIL-10 and/or rTGF-β can inhibit NK cell functions in vitro, providing a potential therapeutic target for strategies aimed at combating HIV infection. [ABSTRACT FROM AUTHOR]

Electronic phase separation (EPS) is a common phenomenon in strongly correlated oxides. For colossal magnetoresistive (CMR) manganites, the EPS is so pronounced that not only does it govern the CMR behavior, but also raises a question whether EPS exists as a ground state for systems or a metastable state. While it has been well known that a magnetic field can drive the transition of the EPS state into a single-phase state in manganites, the reversibility of this transition is not well studied. In this work we use magnetic force microscopy (MFM) to directly visualize the reversibility of the field driven transition between the EPS state and the single-phase state at different temperatures. The MFM images correspond well with the global magnetic and transport property measurements, uncovering the underlying mechanism of the field driven transition between the EPS state and the single-phase state. We argue that EPS state is a consequence of system quenching whose response to an external magnetic field is governed by a local energy landscape. [ABSTRACT FROM AUTHOR]

The article discusses a study which aims to identify the flavonoid compounds found in the aerial parts of Mentha haplocalyx. The study were refluxed with 40% ethanol and diluted with hydrogen oxide. The study uses the mass and nuclear magnetic resonance (NMR) spectroscopy to identify the compounds. Result shows that isoleucanthogenin, apigenin, and tilianin are some of the compounds in the species.

The mol­ecule of the title compound, C12H4Cl2F6N4S, exhibits disorder of both trifluoro­methyl groups. Crystal packing is realised by N—H⋯N hydrogen bonds. [ABSTRACT FROM AUTHOR]