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Background Peroxisome proliferator-activated receptor gamma ( PPAR γ) signaling has been shown to regulate lipogenesis and lipid accumulation. Previous studies have shown that hepatic PPAR γ is up-regulated in steatotic liver of both animal and human. However, the effects of hepatic PPAR γ signaling on alcoholic liver disease ( ALD) remain elusive. Methods To determine the role of hepatic PPAR γ signaling on ALD, wild-type ( WT) and hepatocyte-specific PPAR γ knockdown ( PPAR γ∆ Hep) mice were fed a modified Lieber- De Carli alcohol or isocaloric maltose dextrin control liquid diet for 8 weeks to induce ALD. Blood parameters, hepatic steatosis, and inflammation were measured after 8-week alcohol feeding. Results Alcohol feeding to WT mice resulted in liver damage (alanine aminotransferase [ ALT], 94.68 ± 17.05 U/L; aspartate aminotransferase [ AST], 55.87 ± 11.29 U/L), which was significantly alleviated by hepatic PPAR γ knockdown ( ALT, 57.36 ± 14.98 U/L; AST, 38.06 ± 3.35 U/L). Alcohol feeding led to marked lipid accumulation and up-regulation of lipogenic genes including fatty acid transport protein 1 ( FATP1), acetyl- Co A carboxylase ( ACC), fatty acid synthase ( FASN), lipin1 (LIPIN1), diacylglycerol acyltransferase 1 ( DGAT1), and diacylglycerol acyltransferase 2 ( DGAT2) in the livers of WT mice. Knockdown of hepatic PPAR γ significantly alleviated alcohol-induced lipid accumulation and abolished the up-regulation of FASN, DGAT1, and DGAT2. Silencing of PPAR γ in FL83 B cells significantly decreased ethanol ( Et OH)-, linoleic acid-, and Et OH plus linoleic acid-induced lipid accumulation. Knockdown of hepatic PPAR γ also significantly reduced alcohol-induced inflammatory chemokine (monocyte chemotactic protein 1 [ MCP1], keratinocyte-derived chemokine [ KC], interferon gamma-induced protein 10 [ IP-10]) and inflammatory infiltration (lymphocyte antigen 6 complex, locus G [ Ly6 G], and F4/80). Conclusions The results suggest that hepatic PPAR γ signaling contributes to alcohol-induced liver injury by promoting hepatic steatosis and inflammation. [ABSTRACT FROM AUTHOR]

A series of novel naphthalimide derivatives NI 1-5 containing piperazine moieties ( N-(2-hydroxyethyl)piperazine and 1-piperazinepropanol) and piperidine moieties (4-piperidinemethanol, 4-hydroxypiperidine and 4-piperidineethanol) have been synthesized and evaluated for their cytotoxic activity, spectroscopic property, and DNA binding behaviors. It was found that substituents at the 4-position remarkably influence the various activities of this series of compound. Compounds NI 3-5 modified with piperidines exhibited potent cytotoxic activities against Hela, SGC-7901, and A549 cells with the IC50 values from 0.73 μ m to 6.80 μ m, which are better than NI 1-2 functionalized with piperazines. Compounds NI 1-2 showed higher binding capacity with Ct- DNA than compounds NI 3-5 based on studies of UV-vis, fluorescence and CD spectra. Furthermore, compounds NI 3-5, as DNA intercalators, showed fluorescence enhancement upon binding with Ct- DNA. More interestingly, fluorescence imaging studies of compound NI 4 with A549 cells showed that the fluorescence predominantly appeared in the cytoplasm. These results provided a potential application of NI 3-5 as anticancer therapeutic and cancer cell imaging agents. [ABSTRACT FROM AUTHOR]

1,1-Diamino-2,2-dinitroethylene (FOX-7) is a novel high-energy insensitive material with good thermal stability and low sensitivity, and exhibits excellent application performance in the field of insensitive ammunitions and solid propellant. Although FOX-7 is simple in molecular composition and structure, its chemical reactivity is abundant and surprising, including salification reaction, coordination reaction, nucleophilic substitution reaction, acetylate reaction, oxidizing reaction, reduction reaction, electrophilic addition reaction, among other reactions. These reactions are systemically summarized and some reaction mechanisms are analyzed in this review. [ABSTRACT FROM AUTHOR]

In the present study, rice straw was pretreated using steam-explosion (ST) technique to improve the enzymatic hydrolysis of potential reducing sugars for feed utilization. The response surface methodology based on central composite design was used to optimize the effects of steam pressure, pressure retention time, and straw moisture content on the yield of reducing sugar. All the investigated variables had significant effects (P < 0.001) on the reducing sugar yield. The optimum yield of 30.86% was obtained under the following pretreatment conditions: steam pressure, 1.54 MPa; pressure retention time, 140.5 Sec; and straw moisture content, 41.6%. The yield after thermal treatment under the same conditions was approximately 16%. Infrared (IR) radiation analysis showed a decrease in the cellulose IR crystallization index. ST noticeably increases reducing sugars in rice straw, and this technique may also be applicable to other cellulose/lignin sources of biomass. [ABSTRACT FROM AUTHOR]

Managing the large volumes of data produced by emerging scientific and engineering simulations running on leadership-class resources has become a critical challenge. The data have to be extracted off the computing nodes and transported to consumer nodes so that it can be processed, analyzed, visualized, archived, and so on. Several recent research efforts have addressed data-related challenges at different levels. One attractive approach is to offload expensive input/output operations to a smaller set of dedicated computing nodes known as a staging area. However, even using this approach, the data still have to be moved from the staging area to consumer nodes for processing, which continues to be a bottleneck. In this paper, we investigate an alternate approach, namely moving the data-processing code to the staging area instead of moving the data to the data-processing code. Specifically, we describe the ActiveSpaces framework, which provides (1) programming support for defining the data-processing routines to be downloaded to the staging area and (2) runtime mechanisms for transporting codes associated with these routines to the staging area, executing the routines on the nodes that are part of the staging area, and returning the results. We also present an experimental performance evaluation of ActiveSpaces using applications running on the Cray XT5 at Oak Ridge National Laboratory. Finally, we use a coupled fusion application workflow to explore the trade-offs between transporting data and transporting the code required for data processing during coupling, and we characterize sweet spots for each option. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An aligned and laminated sulfur-absorbed mesoporous carbon/carbon nanotube (CNT) hybrid cathode has been developed for lithium-sulfur batteries with high performance. The mesoporous carbon acts as sulfur host and suppresses the diffusion of polysulfide, while the CNT network anchors the sulfur-absorbed mesoporous carbon particles, providing pathways for rapid electron transport, alleviating polysulfide migration and enabling a high flexibility. The resulting lithium-sulfur battery delivers a high capacity of 1226 mAh g−1 and achieves a capacity retention of 75 % after 100 cycles at 0.1 C. Moreover, a high capacity of nearly 900 mAh g−1 is obtained for 20 mg cm−2, which is the highest sulfur load to the best of our knowledge. More importantly, the aligned and laminated hybrid cathode endows the battery with high flexibility and its electrochemical performances are well maintained under bending and after being folded for 500 times. [ABSTRACT FROM AUTHOR]

How sensory information is processed within olfactory cortices is unclear. Here, we examined long-range circuit wiring between different olfactory cortical regions of acute mouse brain slices using a channelrhodopsin-2 (ChR2)-based neuronal targeting approach. Our results provide detailed information regarding the synaptic properties of the reciprocal long-range monosynaptic glutamatergic projections ( LRMGP) between and within anterior piriform cortex ( aPC), posterior piriform cortex ( pPC), and lateral entorhinal cortex ( LEC), thereby creating a long-range inter- and intracortical circuit diagrams at the level of synapses and single cortical neurons. Our results reveal the following information regarding hierarchical intra- and intercortical organizations: (i) there is massive bottom-up (i.e., rostral-caudal) excitation within the LRMGP accompanied with strong feedforward ( FF) inhibition; (ii) there are convergent FF connections onto LEC from both aPC and pPC; (iii) feedback ( FB) intercortical connections are weak with a significant fraction of presumptive silent synapses; and (iv) intra and intercortical long-range connections lack layer specificity and their innervation of interneurons are stronger than neighboring pyramidal neurons. The elucidation of the distinct hierarchical organization of long-range olfactory cortical circuits paves the way for further understanding of higher order cortical processing within the olfactory system. [ABSTRACT FROM AUTHOR]

Background Chronic alcohol exposure causes lipid dyshomeostasis at the adipose-liver axis, reducing lipid storage in white fat and increasing lipid deposit in the liver. Previous studies have shown that visceral fat, rather than subcutaneous fat, is a risk factor for metabolic diseases. This study was conducted to determine whether chronic alcohol exposure differentially affects lipid metabolism in visceral (epididymal) and subcutaneous fat, and the mechanisms underlying the alcohol effects. Methods Male Wistar rats were pair-fed the Lieber-DeCarli control or alcohol liquid diet for 12 weeks to determine the effects of alcohol on the white fat. Tissue explants culture and 3T3-L1 culture were conducted to define the role of acetaldehyde in alcohol-induced adipose tissue dysfunction. Results Chronic alcohol feeding significantly reduced visceral fat mass and down-regulated peroxisome proliferator activator receptor- γ and CCAAT/enhancer binding protein- α, 2 important transcription factors in regulation of lipogenesis. The protein levels of lipogenic enzymes including phospho- ATP-citrate lyase, acetyl-CoA carboxylase, fatty acid synthase, lipin1, and diacylglycerol acyltransferase 2 in the visceral fat were reduced. In contrast, chronic alcohol exposure did not affect subcutaneous fat mass and had less effect on the protein levels of lipogenic enzymes and regulators. Accordingly, the visceral fat showed a lower protein level of aldehyde detoxification enzymes compared to the subcutaneous fat. Acetaldehyde treatment to either visceral fat explants or 3T3-L1 adipocytes produced similar effects on lipogenic enzymes and regulators as observed in animal model. Conclusions These results demonstrated that visceral fat is more susceptible to alcohol toxicity compared to subcutaneous fat, and disruption of adipose lipogenesis contributes to the pathogenesis of alcoholic lipodystrophy. [ABSTRACT FROM AUTHOR]

The high-energy insensitive compound trifurazano-oxacycloheptatriene (TFO) was first by synthesized through special etherification. The reaction mechanism and reaction conditions were discussed. TFO has a low melting point (78.6 °C) and good compatibility. TFO is insensitive to impact and friction and has similar detonation velocity (7.7 km s−1) and detonation pressure (35.6 GPa) to RDX. [ABSTRACT FROM AUTHOR]

A significant characteristic of cancer cell metabolism is the high level of aerobic glycolysis with high glucose consumption and lactate production. Phophoglycerate mutase 1 (PGAM1) is an enzyme that catalyzes the interconversion of 3-phosphoglycerate and 2-phosphoglycerate during glycolysis. It has been reported that this enzyme is commonly upregulated in many human cancers. PGAM1 plays an important role in coordinating glycolysis and anabolic activity to promote cancer cell proliferation. However, the mechanisms under these effects are still poorly understood. This review focuses on the most recent advances in the structure and functions of PGAM1, and PGAM1's role in glycolysis in cancer cells and regulators that modulate PGAM1's effects. Progress in understanding of PGAM1 will provide the rationale to support the development of new hypothesis-driven studies to define PGAM1's potential therapeutic implications for cancer treatment. [ABSTRACT FROM AUTHOR]

This paper studies the Voronoi diagrams on 2-manifold meshes based on geodesic metric (a.k.a. geodesic Voronoi diagrams or GVDs), which have polyline generators. We show that our general setting leads to situations more complicated than conventional 2D Euclidean Voronoi diagrams as well as point-source based GVDs, since a typical bisector contains line segments, hyperbolic segments and parabolic segments. To tackle this challenge, we introduce a new concept, called local Voronoi diagram (LVD), which is a combination of additively weighted Voronoi diagram and line-segment Voronoi diagram on a mesh triangle. We show that when restricting on a single mesh triangle, the GVD is a subset of the LVD and only two types of mesh triangles can contain GVD edges. Based on these results, we propose an efficient algorithm for constructing the GVD with polyline generators. Our algorithm runs in O(nNlogN) time and takes O(nN) space on an n-face mesh with m generators, where N = max{m, n}. Computational results on real-world models demonstrate the efficiency of our algorithm. [ABSTRACT FROM AUTHOR]

Although previous studies have found that melatonin can promote seed germination, the mechanisms involved in perceiving and signaling melatonin remain poorly understood. In this study, it was found that melatonin was synthesized during cucumber seed germination with a peak in melatonin levels occurring 14 hr into germination. This is indicative of a correlation between melatonin synthesis and seed germination. Meanwhile, seeds pretreated with exogenous melatonin (1 μM) showed enhanced germination rates under 150 mM NaCl stress compared to water-pretreated seeds under salinity stress. There are two apparent mechanisms by which melatonin alleviated salinity-induced inhibition of seed germination. Exogenous melatonin decreased oxidative damage induced by NaCl stress by enhancing gene expression of antioxidants. Under NaCl stress, compared to untreated control, the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were significantly increased by approximately 1.3-5.0-fold, with a concomitant 1.4-2.0-fold increase of CsCu-ZnSOD, CsFe-ZnSOD, CsCAT, and CsPOD in melatoninpretreated seeds. Melatonin also alleviated salinity stress by affecting abscisic acid (ABA) and gibberellin acid (GA) biosynthesis and catabolism during seed germination. Compared to NaCl treatment, melatonin significantly upregulated ABA catabolism genes (e.g., CsCYP707A1 and CsCYP707A2, 3.5 and 105-fold higher than NaCl treatment at 16 hr, respectively) and downregulated ABA biosynthesis genes (e.g., CsNECD2, 0.29-fold of CK2 at 16 hr), resulting in a rapid decrease of ABA content during the early stage of germination. At the same time, melatonin positively up-regulated GA biosynthesis genes (e.g., GA20ox and GA3ox, 2.3 and 3.9-fold higher than NaCl treatment at 0 and 12 hr, respectively), contributing to a significant increase of GA (especially GA4) content. In this study, we provide new evidence suggesting that melatonin alleviates the inhibitory effects of NaCl stress on germination mainly by regulating the biosynthesis and catabolism of ABA and GA4. [ABSTRACT FROM AUTHOR]

GABAergic terminals of chandelier cells exclusively innervate the axon initial segment (AIS) of excitatory neurons. Although the anatomy of these synapses has been well-studied in several brain areas, relatively little is known about their physiological properties. Using vesicular -aminobutyric acid transporter-channelrhodopsin 2-enhanced yellow fluorescence protein (VGAT-ChR2-YFP)-expressing mice and a novel fibreoptic 'laserspritzer' approach that we developed, we investigated the physiological properties of axo-axonic synapses (AASs) in brain slices from the piriform cortex (PC) of mice. AASs were in close proximity to voltage-gated Na+ (NaV) channels located at the AIS. AASs were selectively activated by a 5 µm laserspritzer placed in close proximity to the AIS. Under a minimal laser stimulation condition and using whole-cell somatic voltage-clamp recordings, the amplitudes and kinetics of IPSCs mediated by AASs were similar to those mediated by perisomatic inhibitions. Results were further validated with channelrhodopsin 2-assisted circuit mapping (CRACM) of the entire inhibitory inputs map. For the first time, we revealed that the laserspritzer-induced AAS-IPSCs persisted in the presence of TTX and TEA but not 4-AP. Next, using gramicidin-based perforated patch recordings, we found that theGABA reversal potential (EGABA)was-73.6±1.2mV when induced at the AIS and -72.8 ± 1.1 mV when induced at the perisomatic site. Our anatomical and physiological results lead to the novel conclusions that: (1) AASs innervate the entire length of the AIS, as opposed to forming a highly concentrated cartridge, (2) AAS inhibition suppresses action potentials and epileptiform activity more robustly than perisomatic inhibitions, and (3) AAS activation alone can be sufficient to inhibit action potential generation and epileptiform activities in vitro. [ABSTRACT FROM AUTHOR]

Prostate cancer is a leading cause of cancer-related mortality in men worldwide and there is a lack of effective treatment options for advanced (metastatic) prostate cancer. Currently, limited knowledge is available concerning the role of long non-coding RNAs in prostate cancer metastasis. In this study, we found that long non-coding RNA H19 (H19) and H19-derived microRNA-675 (miR-675) were significantly downregulated in the metastatic prostate cancer cell line M12 compared with the non-metastatic prostate epithelial cell line P69. Upregulation of H19 in P69 and PC3 cells significantly increased the level of miR-675 and repressed cell migration; however, ectopic expression of H19 in M12 cells could not increase the level of miR-675 and therefore had no effect on cell migration. Furthermore, we found that the expression level of either H19 or miR-675 in P69 cells was negatively associated with the expression of transforming growth factor b induced protein (TGFBI), an extracellular matrix protein involved in cancer metastasis. Dual luciferase reporter assays showed that miR-675 directly bound with 30UTR of TGFBI mRNA to repress its translation. Taken together, we show for the first time that the H19-miR-675 axis acts as a suppressor of prostate cancer metastasis, which may have possible diagnostic and therapeutic potential for advanced prostate cancer. [ABSTRACT FROM AUTHOR]

A combination of ab initio calculations, circular dichroism, nuclear magnetic resonance, and X-ray photoelectron spectroscopy has shown that aluminum ions can induce the formation of backbone ring structures in a wide range of peptides, including neurodegenerative disease related motifs. These ring structures greatly destabilize the protein and result in irreversible denaturation. This behavior benefits from the ability of aluminum ions to form chemical bonds simultaneously with the amide nitrogen and carbonyl oxygen atoms on the peptide backbone. [ABSTRACT FROM AUTHOR]

BACKGROUND A blue colour can be formed in the xylose (Xyl) and glycine (Gly) Maillard reaction (MR) model system. However, there are fewer studies on the reaction conditions for the blue Maillard reaction products (MRPs). The objective of this study is to investigate characteristic colour formation and antioxidant activities in four different MR model systems and to determine the optimum reaction conditions for the blue colour formation in a Xyl-Gly MR model system, using the random centroid optimisation program. RESULTS The blue colour with an absorbance peak at 630 nm appeared before browning in the Xyl-Gly MR model system, while no blue colour formation but only browning was observed in the xylose-alanine, xylose-aspartic acid and glucose-glycine MR model systems. The Xyl-Gly MR model system also showed higher antioxidant activity than the other three model systems. The optimum conditions for blue colour formation were as follows: xylose and glycine ratio 1:0.16 (M:M), 0.20 mol L−1 NaHCO3, 406.1 mL L−1 ethanol, initial pH 8.63, 33.7°C for 22.06 h, which gave a much brighter blue colour and a higher peak at 630 nm. CONCLUSION A characteristic blue colour could be formed in the Xyl-Gly MR model system and the optimum conditions for the blue colour formation were proposed and confirmed. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Three new mononuclear cobalt(II) complexes containing ligands with extended planar quinoxaline moieties, {dipyrido[3,2-a:2′,3′-c]phenazine (dppz) or dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq)}, viz. [Co(dppz)(acac)2] · CH3OH ( 1), [Co(dpq)(tfnb)2] ( 2) and [Co(dpq)(dbm)2] ( 3), where acac = acetylacetonate, tfnb = benzoyltrifluoroacetone and dbm = dibenzoylmethane, have been synthesized and structurally characterized as octahedral complexes. The binding ability of the complexes with calf thymus (CT)-DNA has been investigated by spectroscopic and viscosity measurements. Results indicate that all complexes bind to CT-DNA via intercalative mode, and the DNA binding affinity of dppz complex 1 is apparently stronger than that of dpq complexes 2 and 3. Furthermore, DNA photocleavage experiments indicate that these complexes are efficient DNA cleaving agents in UV-A (365 nm) and hydroxyl radical (HO·), singlet oxygen (1O2) and superoxide anion (1O2−) serve as the major cleavage active species. In addition, interaction of the complexes with bovine serum albumin (BSA) was investigated using UV − visible and fluorescence methods, which indicated that all complexes could quench the intrinsic fluorescence of BSA in a static quenching process. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

GaN growth on Si (111) with reduced dislocation density and wafer bow requires the implementation of strain-compensation techniques to counter the thermal expansion mismatch-related tensile stresses. The ability to design the optimal buffer layer strategy for GaN growth on Si (111) relies on the knowledge of the relaxation processes that occur during the growth. In the AlGaN step-graded buffer, the processes are complex, making it difficult to optimize the layer thicknesses, number of layers and compositions. Here, investigation of the relaxation processes as related to the microstructural evolution within the layers is performed. It is found that the use of x-ray diffraction measurements of both line width broadening and relaxation reveal the characteristics of the dominant relaxation process of inclination of edge-type dislocation. The methods and results presented here are expected to aid in the optimization for growth of improved quality and wafer bow-free GaN on Si (111). (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Recent studies suggest that dihydroartemisinin (DHA), a derivative of artemisinin isolated from the traditional Chinese herb Artemisia annua L., has anticancer properties. Due to poor water solubility, poor oral activity, and a short plasma half-life, large doses of DHA have to be injected to achieve the necessary bioavailability. This study examined increasing DHA bioavailability by encapsulating DHA within gelatin (GEL) or hyaluronan (HA) nanoparticles via an electrostatic field system. Observations from transmission electron microscopy show that DHA in GEL and HA nanoparticles formed GEL/DHA and HA/DHA aggregates that were approximately 30-40 nm in diameter. The entrapment efficiencies for DHA were approximately 13 and 35% for the GEL/DHA and HA/DHA aggregates, respectively. The proliferation of A549 cells was inhibited by the GEL/DHA and HA/DHA aggregates. Fluorescent annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) staining displayed low background staining with annexin V-FITC or PI on DHA-untreated cells. In contrast, annexin V-FITC and PI stains dramatically increased when the cells were incubated with GEL/DHA and HA/DHA aggregates. These results suggest that DHA-aggregated GEL and HA nanoparticles exhibit higher anticancer proliferation activities than DHA alone in A549 cells most likely due to the greater aqueous dispersion after hydrophilic GEL or HA nanoparticles aggregation. These results demonstrate that DHA can aggregate with nanoparticles in an electrostatic field environment to form DHA nanosized aggregates. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 455-462, 2014. [ABSTRACT FROM AUTHOR]

This paper investigates-whether liquidity and liquidity risk are priced in Japan. Using modified Amihud illiquidity measures, we find both cross-sectional and time series evidence that liquidity is priced in the Japanese stock market during the period 1975-2006. The evidence is largely consistent with Amihud's (2002) findings in the US market. We further employ the liquidity-adjusted CAPM proposed by Acharya and Pedersen (2005) to examine whether liquidity risk is priced in Japan. Consistent with Acharya and Pedersen's findings in the US, we show that liquidity risk is priced in the stock market, in addition to the liquidity level. These findings strengthen the confidence that liquidity is a determinant of stock returns. [ABSTRACT FROM AUTHOR]

Cucumber is a model cucurbitaceous plant with a known genome sequence which is important for studying molecular mechanisms of root development. In this study, RNA sequencing was employed to explore the mechanism of melatonin-induced lateral root formation in cucumber under salt stress. Three groups of seeds were examined, that is, seeds primed without melatonin ( CK), seeds primed in a solution containing 10 or 500 μmol/L melatonin (M10 and M500, respectively). These seeds were then germinated in NaCl solution. The RNA-seq analysis generated 16,866,670 sequence reads aligned with 17,920 genes, which provided abundant data for the analysis of lateral root formation. A total of 17,552, 17,450, and 17,393 genes were identified from roots of the three treatments ( CK, M10 and M500, respectively). The expression of 121 genes was significantly up-regulated, and 196 genes were significantly down-regulated in M500 which showed an obvious increase on the number of lateral roots. These genes were significantly enriched in 57 KEGG pathways and 16 GO terms (M500 versus CK). Based on their expression pattern, peroxidase-related genes were selected as the candidates to be involved in the melatonin response. Several transcription factor families might play important roles in lateral root formation processes. A number of genes related to cell wall formation, carbohydrate metabolic processes, oxidation/reduction processes, and catalytic activity also showed different expression patterns as a result of melatonin treatments. This RNA-sequencing study will enable the scientific community to better define the molecular processes that affect lateral root formation in response to melatonin treatment. [ABSTRACT FROM AUTHOR]

A single boronic acid-based fluorescent probe (compound CSP) for saccharides was designed and synthesized. The probe, with an α, β-unsaturated ketone conjugated into the coumarin fluorophore, was synthesized by 4 steps from the commercial material 4-diethylamino salicylaldehyde. The electron push-pull effect is enhanced with the N, N-diethyl amino as the electron donor and the carbonyl as the electron acceptor. Both the absorption (463 nm) and emission (616 nm) maxima of CSP are in the visible wavelength region with a Stokes shift of about 150 nm, which ensures CSP a potential probe for biological application. Under near physiological conditions, significant fluorescence enhancement of CSP was observed upon the addition of some saccharides, namely, D-sorbitol, D-fructose, D-glucose, D-mannose and D-galactose. The probe showed relatively high sensitivity towards D-fructose and D-sorbitol, and their detection limits were 0.05 mmol/L and 0.1 mmol/L, respectively. [ABSTRACT FROM AUTHOR]

The association between the interleukin-6 ( IL-6) gene −572 C/G (rs1800796) polymorphism and type 2 diabetes mellitus (T2DM) risk remains controversial. Thus, we performed this meta-analysis by searching PubMed, Embase, Web of Science, CBMdisc and CNKI databases until January 30, 2012. In addition, hand searching of the references of identified articles was performed. A total of 10 case-control studies including 11,681 subjects were selected to evaluate the possible association. Our results showed evidence for significant association between the IL-6 gene −572 C/G polymorphism and T2DM risk (for G allele vs. C allele: odds ratio [OR] = 1.29, 95% confidence interval [CI] = 1.09-1.52, P = 0.002, P = 0.008 after Bonferroni testing; for G/G vs. C/C: OR = 1.89, 95% CI = 1.51-2.37, P < 0.00001, P < 0.00004 after Bonferroni testing; for GG vs. G/C + C/C: OR = 1.75, 95% CI = 1.20-2.56, P = 0.004, P = 0.016 after Bonferroni testing; for G/G + G/C vs. C/C: OR = 1.32, 95% CI = 1.11-1.57, P = 0.001, P = 0.004 after Bonferroni testing). In addition, similar results were obtained in the subgroup analysis based on ethnicity. In summary, the present meta-analysis suggests a significant association between the IL-6 gene −572 G allele and increased risk of T2DM. [ABSTRACT FROM AUTHOR]

A novel method based on high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry was developed for simultaneous determination of the 11 major active components including ten flavonoids and one phenolic acid in Cirsium setosum. Separation was performed on a reversed-phase C18 column with gradient elution of methanol and 0.1‰ acetic acid (v/v). The identification and quantification of the analytes were achieved on a hybrid quadrupole linear ion trap mass spectrometer. Multiple-reaction monitoring scanning was employed for quantification with switching electrospray ion source polarity between positive and negative modes in a single run. Full validation of the assay was carried out including linearity, precision, accuracy, stability, limits of detection and quantification. The results demonstrated that the method developed was reliable, rapid, and specific. The 25 batches of C. setosum samples from different sources were first determined using the developed method and the total contents of 11 analytes ranged from 1717.460 to 23028.258 μg/g. Among them, the content of linarin was highest, and its mean value was 7340.967 μg/g. Principal component analysis and hierarchical clustering analysis were performed to differentiate and classify the samples, which is helpful for comprehensive evaluation of the quality of C. setosum. [ABSTRACT FROM AUTHOR]

Despite extensive research, merger motivation is largely inconclusive. Incomparable methodologies further exacerbate debates in the extant literature. This study uses a recently developed technique to examine post-acquisition evidence as to the motives behind merger and acquisition activity. Using a sample of 3,520 domestic acquisitions in the United States, we find that 73% are related to market timing; 59% are related to agency motives and/or hubris; and 3% are responses to industry and economic shocks. Our results also show that about 80% of the mergers in our sample involved multiple motives. Thus, in general it is very difficult to have a clear picture of merger motivation because value-increasing and value-decreasing motives may coexist. [ABSTRACT FROM AUTHOR]

The importance of epigenetic alterations in the development of various diseases including the cancers has been realized. As epigenetic changes are reversible heritable changes, these can be utilized as an effective strategy for the prevention of cancers. DNA methylation is the most characterized epigenetic mechanism that can be inherited without changing the DNA sequence. Although limited available data suggest that silencing of tumor suppressor genes in ultraviolet (UV) radiation-exposed epidermis leads to photocarcinogenesis and is associated with a network of epigenetic modifications including alterations in DNA methylation, DNA methyltransferases and histone acetylations. Various bioactive dietary components have been shown to protect skin from UV radiation-induced skin tumors in animal models. The role of bioactive dietary components, such as, (−)-epicatechins from green tea and proanthocyanidins from grape seeds has been assessed in chemoprevention of UV-induced skin carcinogenesis and underlying epigenetic mechanism in vitro and in vivo animal models. These bioactive components have the ability to block UV-induced DNA hypermethylation and histone modifications in the skin required for the silencing of tumor suppressor genes ( e.g. Cip1/p21, p16 INK4a). This information is of importance for understanding the role of epigenetic modulation in UV-induced skin tumor and the chemopreventive mechanism of bioactive dietary components. [ABSTRACT FROM AUTHOR]

A new alkaloid, sinoraculine, the precursor of the novel alkaloid sinoracutine, was isolated from the leaves and stems of Stephania cepharantha, and its structure was elucidated by spectroscopic analyses. [ABSTRACT FROM AUTHOR]

Poor earnings quality exacerbates information asymmetry between internal and external stakeholders of a firm. Agency considerations then persuade investors to discount the value of corporate cash holdings out of concern about the inappropriate use of funds. In this study, we show that poor earnings quality has a negative impact on the value of corporate cash holdings and a positive impact on the level of cash reserves. We find that the negative effect of poor earnings quality either neutralizes or more than offsets the positive effect of excess cash on firm value. Our results are robust to several measures of earnings quality and model specifications. [ABSTRACT FROM AUTHOR]

Previous anatomical and physiological studies have established major glutamatergic and GABAergic neuronal subtypes within the piriform cortical circuits. However, quantitative information regarding axo-axonic inhibitory synapses mediated by chandelier cells across major cortical subdivisions of piriform cortex is lacking. Therefore, we examined the properties of these synapses across the entire piriform cortex. Our results show the following. 1) γ-Aminobutyric acid membrane transporter 1-positive varicosities, whose appearance resembles chandelier cartridges, are found around the initial segments of axons of glutamatergic cells across layers II and III. 2) Both the density of axo-axonic cartridges and the degree of γ-aminobutyric acid membrane transporter 1 innervation in each axo-axonic synapse are significantly higher in the piriform cortex than in the neocortex. 3) Glutamate decarboxylase 67, vesicular GABA transporter, and parvalbumin, but not calbindin, are colocalized with the presynaptic varicosities, whereas gephyrin, Na-K-2Cl cotransporter 1, and GABAA receptor α1 subunit, but not K-Cl cotransporter 2, are colocalized at the presumed postsynaptic sites. 4) The axo-axonic cartridges innervate the majority of excitatory neurons and are distributed more frequently in putative centrifugal cells and posterior piriform cortex. We further describe the morphology of chandelier cells by using parvalbumin-immunoreactivity and single-cell labeling. In summary, our results demonstrate that a small population of chandelier cells mediates abundant axo-axonic synapses across the entire piriform cortex. Because of the critical location of these inhibitory synapses in relation to action potential regulation, our results highlight a critical role of axo-axonic synapses in regulating information flow and olfactory-related oscillations within the piriform cortex in vivo. J. Comp. Neurol., 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Summary Porcine haemoglobin, which is normally discarded as a by-product of meat industry, was hydrolysed using pepsin, AS1398 neutrase, trypsin, flavorzyme, papain and alcalase respectively. The peptic hydrolysate exhibited the highest antioxidant activities than those of other hydrolysates, which was separated using ultrafiltration membranes, and consecutively using chromatographic methods including ion-exchange chromatography on SP Sephadex C-25 column, gel filtration chromatography on Sephadex G-25 column and reversed-phase high performance liquid chromatography. Finally, a novel antioxidant peptide from porcine haemoglobin (APPH) was purified, and its sequence was identified to be ARRLGHDFNPDVQAA (1666 Da) using mass spectrometry. APPH exhibited significant higher lipid peroxidation inhibitory ability than that of α-tocopherol as positive control ( P < 0.05), and efficiently quenched hydroxyl radical (IC50 = 26.9 μ m). APPH agrees with the 115-129 residues of the β-chain from porcine haemoglobin. These results indicate that APPH would be a beneficial ingredient for functional food and pharmaceuticals. [ABSTRACT FROM AUTHOR]

ABSTRACT A sensitive and specific method using liquid chromatography-electrospray tandem mass spectrometry (LC-MS/MS) for the determination of pinaverium bromide in human plasma was developed and validated. Pinaverium bromide and an internal standard (paclitaxel) were isolated from plasma samples by precipitating plasma, and determined by LC-MS/MS in multiple-reaction monitoring mode. The main metabolite of pinaverium bromide and endogenous substances in plasma did not show any interference. The calibration curve was linear over the plasma concentration range of 10.0-10000.0 pg/mL with a correlation coefficient of 0.9979. The relative standard derivations intra- and inter-day at 30.0, 300.0 and 8000.0 pg/mL in plasma were less than 15%. The absolute recoveries of pinaverium bromide and the internal standard were 99.7-111.7 and 106.2%, respectively. The lower limit of quantitation was 10 pg/mL. The analytical method was successfully applied to study the pharmacokinetics of pinaverium bromide tablets in healthy Chinese volunteers. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Radical scavenging activity (RSA) of Maillard reaction products (MRPs) made up from porcine haemoglobin hydrolysate (PHH)-sugar model system was tested. RSA of MRPs derived from PHH-xylose system was about fourfold and threefold higher than that of PHH and PHH-glucose MRPs, respectively, which was because of the cyclic form of the xylose. The increase in RSA of MRPs was attributable not only to the sugar type and concentration, but also to the buffer type and temperature. Phosphate buffer was more efficient than citrate or Tris-HCl buffers. As the temperature increase, RSA of MRPs increased and some intermediates polymerised to form brown pigments. Generally, RSA exhibited a significant correlation with the intermediates formation and browning development ( P < 0.05). Electrophoresis study revealed that molecular rearrangements could be involved in the improvement of the RSA. Conjugating PHH with xylose by Maillard reaction is a promising method to improve the RSA of PHH. [ABSTRACT FROM AUTHOR]