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Find video protocols related to scientific articles indexed in Pubmed.
p-Type mesoscopic NiO as an active interfacial layer for carbon counter electrode based perovskite solar cells.
Dalton Trans
PUBLISHED: 11-20-2014
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Replacement of the ZrO2 insulator layer in the state-of-the-art TiO2/ZrO2/carbon structure by mesoscopic p-type NiO particles led to 39% increase of energy conversion efficiency of hole-conductor-free organometallic perovskite heterojunction solar cells with carbon counter electrodes. In these cells, the light absorber, CH3NH3PbI3, formed instantly inside the pores of the entire TiO2/NiO/carbon layer upon sequential deposition of PbI2 and CH3NH3I. Photoluminescence, impedance spectroscopy and transient photovoltage decay measurements have revealed that introduction of NiO extended the electron lifetime and augmented the hole extraction of the counter electrode. As a result, the photocurrent and open-circuit voltage both increased, resulting in a cell with impressive energy conversion efficiency of 11.4% under AM1.5G conditions.
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Extending the shell-isolated nanoparticle-enhanced Raman spectroscopy approach to interfacial ionic liquids at single crystal electrode surfaces.
Chem. Commun. (Camb.)
PUBLISHED: 10-18-2014
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We employ, for the first time, a shell-isolated nanoparticle-enhancement strategy to extend Raman spectroscopy studies to single crystal electrode surfaces in ionic liquids, and combine density functional theory (DFT) calculations to elucidate the structural details of the imidazolium-based ionic liquid-Au single crystal electrode interfaces.
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Plasmonic external cavity laser refractometric sensor.
Opt Express
PUBLISHED: 10-17-2014
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Combining the high sensitivity properties of surface plasmon resonance refractive index sensing with a tunable external cavity laser, we demonstrate a plasmonic external cavity laser (ECL) for high resolution refractometric sensing. The plasmonic ECL utilizes a plasmonic crystal with extraordinary optical transmission (EOT) as the wavelength-selective element, and achieves single mode lasing at the transmission peak of the EOT resonance. The plasmonic ECL refractometric sensor maintains the high sensitivity of a plasmonic crystal sensor, while simultaneously providing a narrow spectral linewidth through lasing emission, resulting in a record high figure of merit for refractometric sensing with an active or passive optical resonator. We demonstrate single-mode and continuous-wave operation of the electrically-pumped laser system, and show the ability to measure refractive index changes with a 3? detection limit of 1.79 × 10-6 RIU. The demonstrated approach is a promising path towards label-free optical biosensing with enhanced signal-to-noise ratios for challenging applications in small molecule drug discovery and pathogen sensing.
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[Medicinal plant hairy roots generating and their applications].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 10-03-2014
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As a kind of the plant tissue cultures, hairy root culture is characterized by rapid growth without exogenous hormones source and high yield of secondary metabolites, which attracted the attention of scholars in resent years. This work systematically summarized the research of medicinal plant hairy roots, including the mechanism, current situation of medicinal plant hairy roots, and their applications.
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Relationship Between LAPTM4B Gene Polymorphism and Susceptibility of Malignant Melanoma in Chinese Patients.
Transl Oncol
PUBLISHED: 10-01-2014
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Lysosomal-associated protein transmembrane 4 beta (LAPTM4B) is known as an oncogene associated with many human malignant tumors. There are two alleles of the gene, LAPTM4B*1 and LAPTM4B*2. Previous studies have shown that LAPTM4B polymorphism contributes to the risk of many cancers. This case-control study was to investigate the relationship between LAPTM4B gene polymorphism and susceptibility of malignant melanoma. The genotypes of LAPTM4B were determined in 617 control subjects and 220 patients with malignant melanoma by utilizing polymerase chain reaction based on specific primers. The genotypic distribution of LAPTM4B and Hardy-Weinberg equilibrium were analyzed by ? (2) test. Odds ratio and 95% confidence interval was calculated by unconditional logistic regression. The distributions of LAPTM4B genotypes were significantly different between melanoma patients (45.9% for *1/1, 46.4% for *1/2 and 7.7 for *2/2) and controls (54.5% for *1/1, 39.9% for *1/2 and 5.7 for *2/2). LAPTM4B *1/2 and LAPTM4B *2/2 had a 1.396-fold and 1.619-fold higher risk for melanoma occurrence than *1/1, and subjects with LAPTM4B*2 have a 1.308-fold higher risk than LAPTM4B*1 carriers. No association between LAPTM4B genotypes and gender, age, subtype, Clark level of invasion, Breslow thickness, ulceration, clinical stage, and C-KIT, BRAF gene mutation status was observed. LAPTM4B*2 is associated with the high risk of malignant melanoma and carrying LAPTM4B *2 may be a susceptible factor to Chinese melanoma patients.
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Efficacy of Heparinoid PSS in Treating Cardiovascular Diseases and Beyond-A Review of 27 Years Clinical Experiences in China.
Clin. Appl. Thromb. Hemost.
PUBLISHED: 09-27-2014
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Propylene glycol alginate sodium sulfate (PSS) is the world's first oral heparinoid approved by Chinese Food and Drug Administration in 1987. Propylene glycol alginate sodium sulfate is produced by modifying partially hydrolyzed alginate, one of the most abundant marine polysaccharides isolated from brown algae, by epoxypropane esterification and by chemical sulfation. It is used for treating and preventing cardiovascular-related diseases. The low cost (US$1.29/100 tablets, ~4 tablets/day), remarkable clinical effects, and convenient oral administration make PSS an ideal long-term prevention drug. Propylene glycol alginate sodium sulfate is available in most drug stores in China, and millions of patients take PSS routinely during the past 27 years. The 22 784 reported clinical cases as well as the structure, preparation, clinical efficacy, adverse reactions, pharmacokinetics, pharmacodynamics, and future perspectives of PSS based on the results of peer-reviewed publications will be discussed. This review should bring the knowledge of PSS gained in China to the world to stimulate in depth academic and clinical studies of PSS.
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Sphingosine-1-phosphate lyase downregulation promotes colon carcinogenesis through STAT3-activated microRNAs.
J. Clin. Invest.
PUBLISHED: 09-25-2014
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Growing evidence supports a link between inflammation and cancer; however, mediators of the transition between inflammation and carcinogenesis remain incompletely understood. Sphingosine-1-phosphate (S1P) lyase (SPL) irreversibly degrades the bioactive sphingolipid S1P and is highly expressed in enterocytes but downregulated in colon cancer. Here, we investigated the role of SPL in colitis-associated cancer (CAC). We generated mice with intestinal epithelium-specific Sgpl1 deletion and chemically induced colitis and tumor formation in these animals. Compared with control animals, mice lacking intestinal SPL exhibited greater disease activity, colon shortening, cytokine levels, S1P accumulation, tumors, STAT3 activation, STAT3-activated microRNAs (miRNAs), and suppression of miR-targeted anti-oncogene products. This phenotype was attenuated by STAT3 inhibition. In fibroblasts, silencing SPL promoted tumorigenic transformation through a pathway involving extracellular transport of S1P through S1P transporter spinster homolog 2 (SPNS2), S1P receptor activation, JAK2/STAT3-dependent miR-181b-1 induction, and silencing of miR-181b-1 target cylindromatosis (CYLD). Colon biopsies from patients with inflammatory bowel disease revealed enhanced S1P and STAT3 signaling. In mice with chemical-induced CAC, oral administration of plant-type sphingolipids called sphingadienes increased colonic SPL levels and reduced S1P levels, STAT3 signaling, cytokine levels, and tumorigenesis, indicating that SPL prevents transformation and carcinogenesis. Together, our results suggest that dietary sphingolipids can augment or prevent colon cancer, depending upon whether they are metabolized to S1P or promote S1P metabolism through the actions of SPL.
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Characterization of eight terpenoids from tissue cultures of the Chinese herbal plant, Tripterygium wilfordii, by high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry.
Biomed. Chromatogr.
PUBLISHED: 09-20-2014
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In this study, a reliable method for analysis and identification of eight terpenoids in tissue cultures of Tripterygium wilfordii has been established using high-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (HPLC-ESI-MS). Our study indicated that sterile seedlings, callus cultures and cell-suspension cultures can rapidly increase the amount of biological materials. HPLC-ESI-MS was used to identify terpenoids from the extracts of these tissue cultures. Triptolide, triptophenolide, celastrol and wilforlide A were unambiguously determined by comparing the retention times, UV spectral data, and mass fragmentation behaviors with those of the reference compounds. Another four compounds were tentatively identified as triptonoterpenol, triptonoterpene, 22?-hydroxy-3-oxoolean-12-en-29-oic acid and wilforlide B, based on their UV and mass spectrometry spectra. The quantitative analysis showed that all three materials contain triptolide, triptophenolide, celastrol, wilforlide A, and the contents of the four compounds in the cell-suspension cultures were 53.1, 240, 129 and 964?µg/g, respectively, which were at least 2.0-fold higher than these in the sterile seedlings and callus cultures. Considering the known pharmacological activity of triptolide and celastrol, we recommend the cell-suspension cultures as biological materials for future studies, such as clinical and toxicological studies. The developed method was validated by the evaluation of its precision, linearity, detection limits and recovery, and it was successfully used to identify and quantify the terpenoids in the tissue cultures.
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[Study of fast pretreatment method in detection of melamine in liquid milk using liquid chromatography and Raman spectroscopy].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-12-2014
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The present paper proposed for the first time the flocculation-filtration method for separation of interfering substances in milk, such as fat. In this method only two steps were carried out. Firstly, aluminum chloride (PAC, Al2 (OH)nCl6-n,) is used to flocculate the milk; Secondly, water filter was used to filter the mixture. Then the clear filtrate could be used for the detection of melamine. The whole preprocessing would not take more than one minute. The pretreatment process was optimized. Experiments show that the adding proportion of PAC should be about 2%-3% for best filtration efficiency, and that it would have the best flocculation effect when the mixture was mildly alkaline. High performance liquid chromatography experiments show that the melamine recovery of this method is more than 90%. Samples pretreated by the flocculation--filtration method were clearer and the baselines of spectral curve obtained by sensitizing Raman method were more smooth which means better purification compared to those samples pretreated by centrifugal pretreatment method. The pretreatment method proposed can be used in HPLC and Raman spectroscopy methods for rapid detecting melamine in liquid milk. This method shows better separation effect, simpler operation, and lower time and money cost than those pretreatment processes in the existing standard melamine detection method for milk. By use of this pretreatment method, the melamine rapid detection efficiency would be greatly improved.
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Characterization of nitrogen-rich biomaterial-derived biochars and their sorption for aromatic compounds.
Environ. Pollut.
PUBLISHED: 09-03-2014
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Biochars from nitrogen-rich biomaterials (i.e., ?-amylase, chitin and zein) were produced at different temperatures (i.e. 170, 250, 350 and 450 °C) and characterized, and their sorption for phenanthrene, naphthalene and 1-naphthol was investigated. The organic carbon content normalized-sorption coefficient (Koc) of the tested compounds by biochars increased with increasing charring temperature, attributed to the reduction of O-containing polar moieties especially the O-alkyl components, and the newly created aromatic carbon domains. The N-heterocyclic ring structure formed during charring process may enhance ?-? interactions between aromatics and the aromatic components in the resulting biochars. However, ?-? interactions did not dominate sorption of aromatics by N-rich biochars. Sorption of the tested compounds by N-rich biochars was predominantly controlled by the hydrophobic interactions between these chemicals and the aromatic components in biochars. Both N- and O-containing polar moieties at the biochar surfaces negatively affected their sorption for aromatics.
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Osteogenic properties of PBLG-g-HA/PLLA nanocomposites.
PLoS ONE
PUBLISHED: 09-03-2014
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New development of biomaterial scaffolds remains a prominent issue for the regeneration of lost or fractured bone. Of these scaffolds, a number of bioactive polymers have been synthesized and fabricated for diverse biological roles. Although recent evidence has demonstrated that composite scaffolds such as HA/PLLA have improved properties when compared to either HA or PLLA alone, recent investigations have demonstrated that the phase compatibility between HA and PLLA layers is weak preventing optimal enhancement of the mechanical properties and making the composites prone to breakdown. In the present study, poly (?-benzyl-L-glutamate) modified hydroxyapatite/(poly (L-lactic acid)) (PBLG-g-HA/PLLA) composite scaffolds were fabricated with improved phase compatibility and tested for their osteogenic properties in 18 Wistar female rats by analyzing new bone formation in 3 mm bilateral femur defects in vivo. At time points, 2, 4 and 8 weeks post surgery, bone formation was evaluated by µ-CT and histological analysis by comparing 4 treatment groups; 1) blank defect, 2) PLLA, 3) HA/PLLA and 4) PBLG-g-HA/PLLA scaffolds. The in vivo analysis demonstrated that new bone formation was much more prominent in HA/PLLA and PBLG-g-HA/PLLA groups as depicted by µ-CT, H&E staining and immunohistochemistry for collagen I. TRAP staining was also utilized to determine the influence of osteoclast cell number and staining intensity to the various scaffolds. No significant differences in either staining intensity or osteoclast numbers between all treatment modalities was observed, however blank defects did contain a higher number of osteoclast-like cells. The results from the present study illustrate the potential of PBLG-g-HA/PLLA scaffolds for bone tissue engineering applications by demonstrating favorable osteogenic properties.
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20(s)-ginsenoside Rg3 promotes apoptosis in human ovarian cancer HO-8910 cells through PI3K/Akt and XIAP pathways.
Tumour Biol.
PUBLISHED: 08-29-2014
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Ovarian cancer is a serious tumor which represents a great threat to women's health. Recently, researchers had found that 20(s)-ginsenoside Rg3 could inhibit growth of several cancer cell lines; however, the mechanism is not fully understood so far. In the present study, we found that 20(s)-ginsenoside Rg3 reduced cell viability and induced apoptosis in a dose- and time-dependent manner in the human ovarian cancer cells HO-8910. The induction of apoptosis was accompanied by downregulation of phosphatidylinositol 3-kinase (PI3K)/Akt family proteins and inhibitor of apoptosis protein (IAP) family proteins. 20(s)-ginsenoside Rg3 treatment resulted in activation of caspase-3 and -9, which may partly explain the anti-cancer activity of 20(s)-ginsenoside Rg3. Taken together, our study for the first time suggests that 20(s)-ginsenoside Rg3 is able to enhance apoptosis of HO-8910 cells, at least in part, through downregulation of PI3K/Akt and IAP family proteins. Moreover, the triggering of caspase-3 and -9 activation mediated apoptotic induction. Our data indicate that 20(s)-ginsenoside Rg3 is an effective apoptosis-inducing natural compound in ovarian cancer cells and may have a role in future therapies for ovarian cancer.
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The association between leukoaraiosis and carotid atherosclerosis: a systematic review and meta-analysis.
Int. J. Neurosci.
PUBLISHED: 08-28-2014
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The association between large-artery atherosclerosis and leukoaraiosis (LA) has been increasingly reported with inconsistent conclusion. This systematic review examines the relationship between LA and carotid atherosclerosis, manifested as atherosclerotic stenosis, plaques and increased intima-media thickness (IMT). PubMed, Embase, and Web of Science were searched for articles published up to February 2014. Thirty-two studies that examined the relationship between LA and carotid atherosclerosis were included. All statistical analysis was conducted with Review Manager 5.2.4. Finally, 32 studies including 17,721 patients were identified. There were 7 (30%) out of 23 studies reporting significant association between LA and carotid stenosis; 11 (79%) out of 14 studies reporting significant association between LA and carotid plaque; all 9 studies reporting significant association between LA and carotid IMT; one study showing an association between LA and CAWT (similar to the role of the IMT). The quantitative meta-analysis of 10 studies showed that carotid atherosclerosis was not associated with LA (OR: 1.10; 95% CI: 0.61-1.98). A significant association was found between LA and carotid plaque (OR = 3.53; 95% CI = 1.83-6.79), and the result of IMT group showed that IMT increased risk of LA (MD = 0.11; 95% CI = 0.01-0.22). This systematic review suggested that LA has a tendency of association with carotid plaques but no association with simple carotid stenosis.
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Composition-dependent photoluminescence intensity and prolonged recombination lifetime of perovskite CH3NH3PbBr(3-x)Cl(x) films.
Chem. Commun. (Camb.)
PUBLISHED: 08-22-2014
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Mixed halide perovskites CH3NH3PbBr3-xClx (x = 0.6-1.2) with different compositions of halogens exhibit drastically changed optical properties. In particular, the thin films prepared with these perovskites demonstrate extraordinary photoluminescence emission intensities and prolonged recombination lifetimes up to 446 ns, which are desirable for light emitting and photovoltaic applications.
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Highly sensitive assay for acetylcholinesterase activity and inhibition based on a specifically reactive photonic nanostructure.
ACS Appl Mater Interfaces
PUBLISHED: 08-22-2014
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Assays for acetylcholinesterase (AChE) with high sensitivity and high selectivity as well as facile manipulation have been urgently required in various fields. In this work, a reaction-based photonic strategy was developed for the efficient assay of AChE activity and inhibition based on the synergetic combination of the specific thiol-maleimide addition reaction with photonic porous structure. It was found that various applications including detection of AChE activity, measurement of the related enzymatic kinetics, and screening of inhibitors could be efficiently implemented using such strategy. Remarkably, the unique photonic nanostructure endows the constructed sensing platform with high sensitivity with a limit of detection (LOD) of 5 mU/mL for AChE activity, high selectivity, and self-reporting signaling. Moreover, the label-free solid film-based sensing approach described here has advantages of facile manipulation and bare-eye readout, compared with conventional liquid-phase methods, exhibiting promising potential in practical application for the AChE assay.
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The association between single nucleotide polymorphisms of GSK 3? gene and sporadic alzheimer's disease in a cohort of southern Chinese Han population.
Neurotox Res
PUBLISHED: 08-21-2014
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Recent studies suggest that genetic factors contribute to the pathogenesis of sporadic Alzheimer's disease (sAD). Glycogen synthase kinase-3 beta (GSK 3?) is an important molecule which regulates tau phosphorylation and neurofibrillary tangles formation. GSK 3? gene may be a potential candidate gene for the risk of sAD. To investigate the association of the polymorphisms in GSK 3? gene with sAD, we conducted a case-control study in a southern Chinese Han cohort including 302 sAD patients and 315 control participants. Four single nucleotide polymorphisms (SNPs) (rs3732361, rs56728675, rs60393216, and rs334558) within the promoter region of GSK 3? gene were selected and genotyped with a polymerase chain reaction-ligase detection (PCR-LDR) method. Logistic regression was used to analyze the association between target SNPs and the risk of sAD. After adjusting for age, sex, and APOE ?4 status, no association was revealed between these SNPs and sAD (P > 0.05). The SNPs in the selected regions of GSK 3? gene are unlikely to confer the susceptibility of sAD in southern Chinese Han population. Further studies with a larger sample size and different ethnic populations are needed to reveal the role of SNPs of GSK 3? gene in the pathogenesis of sAD.
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Luteolin from Flos Chrysanthemi and its derivatives: New small molecule Bcl-2 protein inhibitors.
Bioorg. Med. Chem. Lett.
PUBLISHED: 08-20-2014
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Over-expression of the Bcl-2 anti-apoptotic proteins is closely related to tumorigenesis and associated with drug resistance. Here we report that luteolin, a main substance found in Flos Chrysanthemi, directly binds to and shows inhibitory activity against the Bcl-2 protein. We studied the binding mode of luteolin and its derivatives with target proteins, their structure-activity relationship, and their effect on the human leukemia cell line HL-60. The results suggest that luteolin and its derivatives with a benzyl group introduced to the B ring, are new small molecule Bcl-2 protein inhibitors, and their anti-tumor activity is likely related to their effect on the Bcl-2 protein.
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When you smile, you become happy: Evidence from resting state task-based fMRI.
Biol Psychol
PUBLISHED: 08-17-2014
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Simulation studies on emotion have shown that facial actions can initiate and modulate particular emotions. However, the neural mechanisms of these initiating and modulating functions are unclear. In this study, we used resting-state functional magnetic resonance imaging (fMRI) and task-based fMRI to explore these processes by examining spontaneous cerebral activities and brain activations under two conditions: holding a pen using only the teeth (HPT: facilitating the muscles typically associated with smiling) and holding a pen using only the lips (HPL: inhibiting the muscles typically associated with smiling). The resting-state fMRI results showed that compared with the HPL condition, significant increases in the amplitudes of low-frequency fluctuations were found in the right posterior cingulate gyrus [PCG; Brodmann area 31 (BA31)] and in the left middle frontal gyrus (MFG; BA9) in the HPT condition. These findings might be related to the initiation of positive emotions (PCG) and to the control and allocation of attention (MFG). The task-based fMRI results showed that the inferior parietal lobule, left supplementary motor area, superior parietal lobule, precuneus, and bilateral middle cingulum were active when facial manipulation influenced the recognition of emotional facial expressions. These results demonstrate that facial actions might not only initiate a particular emotion and draw attention, but also influence face-based emotion recognition.
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Ubiquitin-specific protease 2b negatively regulates IFN-? production and antiviral activity by targeting TANK-binding kinase 1.
J. Immunol.
PUBLISHED: 07-28-2014
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TANK-binding kinase 1 (TBK1) is essential for IFN regulatory factor 3 activation and IFN-? production downstream of various innate receptors. However, how TBK1 activation is terminated is not well defined. In this study, we identified ubiquitin-specific protease (USP) 2b as a new negative regulator for TBK1 activation. Overexpression of USP2b inhibited retinoic acid-inducible gene-I-mediated IFN-? signaling; in contrast, knockdown of USP2b expression by small interfering RNA enhanced retinoic acid-inducible gene-I-mediated IFN-? signaling. Coimmunoprecipitation experiments demonstrated that USP2b interacted with TBK1. As a deubiquitinating enzyme, USP2b was demonstrated to cleave K63-linked polyubiquitin chains from TBK1 to inhibit TBK1 kinase activity. Consistent with the inhibitory roles of USP2b on TBK1 activation, knockdown of USP2b significantly inhibited the replication of vesicular stomatitis virus, whereas overexpression of USP2b resulted in enhanced replication of vesicular stomatitis virus. Therefore, our findings demonstrated that USP2b deubiquitinates K63-linked polyubiquitin chains from TBK1 to terminate TBK1 activation and negatively regulate IFN-? signaling and antiviral immune response.
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Waltonitone induces apoptosis through mir-663-induced Bcl-2 downregulation in non-small cell lung cancer.
Tumour Biol.
PUBLISHED: 07-24-2014
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Our previous study reported that waltonitone treatment inhibited proliferation and induced apoptosis of lung cancer cells. However, the mechanism of waltonitone-induced toxicity remains unclear. In the present study, we treated H460 and H3255 lung cancer cells using different concentration of waltonitone (0, 10, 20, 30 ?mol/L). We observed that waltonitone inhibited cell viability and induced apoptosis in a concentration dependent manner, with upregulation of caspase-3 cleavage. We also observed upregulation of miR-663, a potential tumor suppressor, after waltonitone treatment. Suppression of miR-663 function using miR-663 inhibitor partly alleviated cell toxicity induced by waltonitone. In addition, both waltonitone treatment and transfection of miR-663 mimic upregulated Bcl-2 mRNA and protein expression. Bcl-2 transfection alleviated waltonitone-induced toxicity. Furthermore, transfection of miR-663 inhibitor upregulated Bcl-2 levels in both cell lines. In summary, the present study demonstrated that waltonitone induced apoptosis of lung cancer cells through, at least partly, miR-663-induced Bcl-2 downregulation.
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Cucurbitacin B inhibits proliferation and induces apoptosis via STAT3 pathway inhibition in A549 lung cancer cells.
Mol Med Rep
PUBLISHED: 07-21-2014
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Natural products are a great source of cancer chemotherapeutic agents. The present study was conducted to investigate whether cucurbitacin B (CuB), one of the most potent and widely used cucurbitacins, inhibits proliferation and induces apoptosis in the A549 lung cancer cell line. Furthermore, CuB induced apoptosis of A549 cells in a -concentration-dependent manner, as determined by fluorescence microscopy, flow cytometry and transmission electron microscopy. The present study also demonstrated that CuB dose-dependently inhibited lung cancer cell proliferation, with cell cycle inhibition and cyclin B1 downregulation. Apoptosis induced by CuB was shown to be associated with cytochrome c release, B-cell lymphoma 2 downregulation and signal transducer and activator of transcription 3 pathway inhibition. CuB may prove to be a useful approach for the chemotherapy of lung cancer.
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Study of droplet formation process during drop-on-demand inkjetting of living cell-laden bioink.
Langmuir
PUBLISHED: 07-21-2014
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Biofabrication offers a great potential for the fabrication of three-dimensional living tissues and organs by precisely layer-by-layer placing various tissue spheroids as anatomically designed. Inkjet printing of living cell-laden bioink is one of the most promising technologies enabling biofabrication, and the bioink printability must be carefully examined for it to be a viable biofabrication technology. In this study, the cell-laden bioink droplet formation process has been studied in terms of the breakup time, droplet size and velocity, and satellite formation using a time-resolved imaging approach. The bioink has been prepared using fibroblasts and sodium alginate with four different cell concentrations: without cells, 1 × 10(6), 5 × 10(6), and 1 × 10(7) cells/mL to appreciate the effect of cell concentration on the droplet formation process. Furthermore, the bioink droplet formation process is compared with that during the inkjetting of a comparable polystyrene microbead-laden suspension under the identical operating conditions to understand the effect of particle physical properties on the droplet formation process. It is found that (1) as the cell concentration of bioink increases, the droplet size and velocity decrease, the formation of satellite droplets is suppressed, and the breakup time increases, and (2) compared to the hard bead-laden suspension, the bioink tends to have a less ejected fluid volume, lower droplet velocity, and longer breakup time.
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Stable and Low-Cost Mesoscopic CH3 NH3 PbI2 Br Perovskite Solar Cells by using a Thin Poly(3-hexylthiophene) Layer as a Hole Transporter.
Chemistry
PUBLISHED: 07-15-2014
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Mesoscopic perovskite solar cells using stable CH3 NH3 PbI2 Br as a light absorber and low-cost poly(3-hexylthiophene) (P3HT) as hole-transporting layer were fabricated, and a power conversion efficiency of 6.64?% was achieved. The partial substitution of iodine with bromine in the perovskite led to remarkably prolonged charge carrier lifetime. Meanwhile, the replacement of conventional thick spiro-MeOTAD layer with a thin P3HT layer has significantly reduced the fabrication cost. The solar cells retained their photovoltaic performance well when they were exposed to air without any encapsulation, presenting a favorable stability. The combination of CH3 NH3 PbI2 Br and P3HT may render a practical and cost-effective solid-state photovoltaic system. The superior stability of CH3 NH3 PbI2 Br is also promising for other photoconversion applications.
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Inhibition of TNF-? in hypothalamic paraventricular nucleus attenuates hypertension and cardiac hypertrophy by inhibiting neurohormonal excitation in spontaneously hypertensive rats.
Toxicol. Appl. Pharmacol.
PUBLISHED: 07-12-2014
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We hypothesized that chronic inhibition of tumor necrosis factor-alpha (TNF-?) in the hypothalamic paraventricular nucleus (PVN) delays the progression of hypertension and attenuates cardiac hypertrophy by up-regulating anti-inflammatory cytokines, reducing pro-inflammatory cytokines (PICs), decreasing nuclear factor-?B (NF-?B) p65 and NAD(P)H oxidase activities, as well as restoring the neurotransmitters balance in the PVN of spontaneously hypertensive rats (SHR). Adult normotensive Wistar-Kyoto (WKY) and SHR rats received bilateral PVN infusion of a TNF-? blocker (pentoxifylline or etanercept) or vehicle for 4weeks. SHR rats showed higher mean arterial pressure and cardiac hypertrophy compared with WKY rats, as indicated by increased whole heart weight/body weight ratio, whole heart weight/tibia length ratio, left ventricular weight/tibia length ratio, and cardiac atrial natriuretic peptide (ANP) and beta-myosin heavy chain (?-MHC) mRNA expressions. Compared with WKY rats, SHR rats had higher PVN levels of tyrosine hydroxylase, PICs, the chemokine monocyte chemoattractant protein-1 (MCP-1), NF-?B p65 activity, mRNA expressions of NOX-2 and NOX-4, and lower PVN levels of IL-10 and 67-kDa isoform of glutamate decarboxylase (GAD67), and higher plasma norepinephrine. PVN infusion of pentoxifylline or etanercept attenuated all these changes in SHR rats. These findings suggest that SHR rats have an imbalance between excitatory and inhibitory neurotransmitters, as well as an imbalance between pro- and anti-inflammatory cytokines in the PVN; and chronic inhibition of TNF-? in the PVN delays the progression of hypertension by restoring the balances of neurotransmitters and cytokines in the PVN, and attenuating PVN NF-?B p65 activity and oxidative stress, thereby attenuating hypertension-induced sympathetic hyperactivity and cardiac hypertrophy.
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[Effects of leukotriene D4 on proliferation and migration of lung epithelial A549 cells in vitro].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 07-08-2014
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To investigate the effects of cysteinyl leukotriene ?CysLT? receptor agonist leukotriene D4 ?LTD4? on proliferation and migration in lung epithelial A549 cells.
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Amygdala NRG1-ErbB4 Is Critical for the Modulation of Anxiety-Like Behaviors.
Neuropsychopharmacology
PUBLISHED: 07-03-2014
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Anxiety disorder is related to the pathophysiology of psychiatric diseases, including major depression, substance abuse, and schizophrenia. The amygdala is important for manifestation and modulation of anxiety. However, relatively little is known regarding the mechanisms that control the amygdala inhibitory activity that is involved in anxiety. We found that almost all ErbB4, which is the only autonomous receptor of neuregulin 1 (NRG1) in the basolateral amygdala (BLA), was expressed in GABAergic neurons. Endogenous NRG1-ErbB4 signaling pathway in the BLA could modulate anxiety-like behaviors and GABA release, whereas it had no effect on glutamatergic transmission. The administration of NRG1 into the BLA of high-anxiety mice alleviated their anxiety and enhanced GABAergic neurotransmission. Moreover, exogenous NRG1 also produced an anxiolytic effect in the stressed mice. Together, these observations indicated that NRG1-ErbB4 signaling is critical to maintaining GABAergic activity in the amygdala and thus to modulating anxiety-like behaviors. Because NRG1 and ErbB4 are susceptibility genes of schizophrenia, our findings might also help to explain the potential mechanism of emotional abnormality in schizophrenia.Neuropsychopharmacology advance online publication, 19 November 2014; doi:10.1038/npp.2014.274.
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PPAR? Agonist Fenofibrate Ameliorates Learning and Memory Deficits in Rats Following Global Cerebral Ischemia.
Mol. Neurobiol.
PUBLISHED: 06-19-2014
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Increasing evidence demonstrates that local inflammation contributes to neuronal death following cerebral ischemia. Peroxisome proliferator-activated receptor ? (PPAR?) activation has been reported to exhibit many pharmacological effects including anti-inflammatory functions. The aim of this study was to investigate the neuroprotective effects of PPAR? agonist fenofibrate on the behavioral dysfunction induced by global cerebral ischemia/reperfusion (GCI/R) injury in rats. The present study showed that fenofibrate treatment significantly reduced hippocampal neuronal death, and improved memory impairment and hippocampal neurogenesis after GCI/R. Fenofibrate administration also inhibited GCI/R-induced over-activation of microglia but not astrocytes and prevented up-regulations of pro-inflammatory mediators in hippocampus. Further study demonstrated that treatment with fenofibrate suppressed GCI/R-induced activations of P65 NF-?B and P38 MAPK. Our data suggest that the PPAR? agonist fenofibrate can exert functional recovery of memory deficits and neuroprotective effect against GCI/R in rats via triggering of neurogenesis and anti-inflammatory effect mediated by inhibiting activation of P65 NF-?B and P38 MAPK in the hippocampus, which can contribute to improvement in neurological deficits.
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Angiotensin(1-7) attenuates the progression of streptozotocin-induced diabetic renal injury better than angiotensin receptor blockade.
Kidney Int.
PUBLISHED: 06-16-2014
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To explore the potential therapeutic effects of angiotensin(1-7) (Ang(1-7)), an endogenous ligand of the Mas receptor, on streptozotocin-induced diabetic nephropathy, male Wistar rats were randomly divided into two groups: a control group and a diabetic model group. After 12 weeks, the diabetic rats were divided into subgroups for 4-week treatments consisting of no-treatment group, small-, moderate-, and large-dose Ang(1-7) groups, a valsartan group, a large-dose Ang(1-7) plus valsartan group, and an A779 (antagonist of the Mas receptor) group, each with 15 rats. Ang(1-7) improved renal function, attenuated glomeruli sclerosis, oxidative stress, and cell proliferation, decreased the expression of collagen IV, TGF-?1, VEGF, NOX4, p47phox, PKC?, and PKC?1, and the phosphorylation of Smad3. In the rat mesangial HBZY-1 cell line, Ang(1-7) decreased high-glucose-induced oxidative stress, the proliferation and expression of NOX4, p47phox, and TGF-?1, the phosphorylation of Smad3, collagen IV, and VEGF, and the membrane translocation of PKC? and PKC?1. A779 blocked the effects of Ang(1-7) both in vivo and in vitro. The effects of large-dose Ang(1-7) alone and in combination with valsartan were superior to valsartan alone, but the combination had no significant synergistic effect compared with Ang(1-7) alone. Thus, Ang(1-7) ameliorated streptozotocin-induced diabetic renal injury. Large-dose treatment was superior to valsartan in reducing oxidative stress and inhibiting TGF?1/Smad3- and VEGF-mediated pathways.Kidney International advance online publication, 30 July 2014; doi:10.1038/ki.2014.274.
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[Automated proton magnetic resonance spectroscopy imaging guided frameless stereotactic biopsy of intracranial lesions].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 06-14-2014
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To evaluate the feasibility, reliability and accuracy of the automated magnetic resonance spectroscopy ((1)H-MRS) guided frameless brain biopsy with intraoperative magnetic resonance imaging (iMRI).
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Flexible Organic Electronics in Biology: Materials and Devices.
Adv. Mater. Weinheim
PUBLISHED: 06-13-2014
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At the convergence of organic electronics and biology, organic bioelectronics attracts great scientific interest. The potential applications of organic semiconductors to reversibly transmit biological signals or stimulate biological tissues inspires many research groups to explore the use of organic electronics in biological systems. Considering the surfaces of movable living tissues being arbitrarily curved at physiological environments, the flexibility of organic bioelectronic devices is of paramount importance in enabling stable and reliable performances by improving the contact and interaction of the devices with biological systems. Significant advances in flexible organic bio-electronics have been achieved in the areas of flexible organic thin film transistors (OTFTs), polymer electrodes, smart textiles, organic electrochemical ion pumps (OEIPs), ion bipolar junction transistors (IBJTs) and chemiresistors. This review will firstly discuss the materials used in flexible organic bioelectronics, which is followed by an overview on various types of flexible organic bioelectronic devices. The versatility of flexible organic bioelectronics promises a bright future for this emerging area.
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The M-T hook structure increases the potency of HIV-1 fusion inhibitor sifuvirtide and overcomes drug resistance.
J. Antimicrob. Chemother.
PUBLISHED: 06-07-2014
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Peptides derived from the C-terminal heptad repeat (CHR) of HIV-1 gp41 are potent fusion inhibitors. We have recently demonstrated that the unique M-T hook structure preceding the pocket-binding motif of CHR peptide-based inhibitors can greatly improve their antiviral activity. In this study, we applied the M-T hook structure to optimize sifuvirtide (SFT), a potent CHR-derived inhibitor currently under Phase III clinical trials in China.
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Photoelectrocatalytic reduction of CO2 into chemicals using Pt-modified reduced graphene oxide combined with Pt-modified TiO2 nanotubes.
Environ. Sci. Technol.
PUBLISHED: 05-28-2014
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The photoelectrocatalytic (PEC) reduction of CO2 into high-value chemicals is beneficial in alleviating global warming and advancing a low-carbon economy. In this work, Pt-modified reduced graphene oxide (Pt-RGO) and Pt-modified TiO2 nanotubes (Pt-TNT) were combined as cathode and photoanode catalysts, respectively, to form a PEC reactor for converting CO2 into valuable chemicals. XRD, XPS, TEM, AFM, and SEM were employed to characterize the microstructures of the Pt-RGO and Pt-TNT catalysts. Reduction products, such as C2H5OH and CH3COOH, were obtained from CO2 under band gap illumination and biased voltage. A combined liquid product generation rate (CH3OH, C2H5OH, HCOOH, and CH3COOH) of approximately 600 nmol/(h·cm(2)) was observed. Carbon atom conversion rate reached 1,130 nmol/(h·cm(2)), which were much higher than those achieved using Pt-modified carbon nanotubes and platinum carbon as cathode catalysts.
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Association between intercellular adhesion molecule-1 gene K469E polymorphism and the risk of stroke in a Chinese population: a meta-analysis.
Int. J. Neurosci.
PUBLISHED: 05-03-2014
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Several epidemiologic studies have evaluated the association between intercellular adhesion molecule-1 (ICAM-1) gene K469E polymorphism and stroke, but the results were inconsistent. The present meta-analysis was performed to investigate the relationship between K469E polymorphism and stroke in the Chinese population. A comprehensive search for related studies from the electronic databases of PubMed, Embase, Web of Science, CBMdisc and CNKI as well as a manual search of the references of identified articles was performed. Data were extracted to calculate for allelic, additive, dominant and recessive models using pooled odds ratios (ORs) along with 95% confidence intervals (CIs) by Review Manager 5.0 and Stata 11.0. Different effect models, subgroup analysis, sensitivity analysis, publication bias and power calculations were used to improve the comprehensive analysis. Finally, a total of 12 studies containing 1593 cases and 1555 controls were included in the final meta-analysis. No evidence of significant association between ICAM-1 gene K469E polymorphism and stroke was found in all four models (allelic model: OR = 1.07, 95%CI = 0.78-1.47; additive model: OR = 1.21, 95% CI = 0.67-2.16 (EE vs. KK); OR = 1.04, 95%CI = 0.75-1.45 (EK vs. KK); dominant model: OR = 1.07, 95% CI = 0.73-1.56; and recessive model: OR = 1.18, 95% CI = 0.77-1.83, respectively) based on the overall population, as well as subgroup analysis and sensitivity analysis. In conclusion, the present meta-analysis showed no evidence of significant association between ICAM-1 gene K469E polymorphism and stroke in the Chinese population. Nonetheless, this conclusion should be interpreted cautiously due to the low statistical power and considerable heterogeneity. Therefore, larger sample-size studies with homogeneous cases and well-matched controls are needed to further address this correlation.
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Endothelial progenitor cells as a possible component of stem cell niche to promote self-renewal of mesenchymal stem cells.
Mol. Cell. Biochem.
PUBLISHED: 04-28-2014
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Stem cells dwell at the "stem cell niche" to accomplish a series of biological processes. The composition of the niche should be determined because the insufficient understanding of this feature limits the development in the study of stem cells. We showed in our study on mesenchymal stem cells (MSCs) that the MSCs first neighbored to CD31(+) cells, which proved to be endothelial progenitor cells (EPCs), and formed a group of cell colony before they exerted their biological functions. It was further proved that EPCs have close interactions with MSCs and promoted the self-renewal of the MSCs in vitro and in vivo. Together with these achievements, we hypothesized that EPCs may be a possible biological component of the MSC stem cell niche and affect the biological processes of MSCs.
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Effects of two amino acid substitutions in the capsid proteins on the interaction of two cell-adapted PanAsia-1 strains of foot-and-mouth disease virus serotype O with heparan sulfate receptor.
Virol. J.
PUBLISHED: 04-23-2014
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Some cell-adapted strains of foot-and-mouth disease virus (FMDV) can utilize heparan sulfate (HS) as a receptor to facilitate viral infection in cultured cells. A number of independent sites on the capsid that might be involved in FMDV-HS interaction have been studied. However, the previously reported residues do not adequately explain HS-dependent infection of two cell-adapted PanAsia-1 strains (O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc) of FMDV serotype O. To identify the molecular determinant(s) for the interaction of O/Tibet/CHA/6/99tc and O/Fujian/CHA/9/99tc with HS receptor, several chimeric viruses and site-directed mutants were generated by using an infectious cDNA of a non-HS-utilizing rescued virus (Cathay topotype) as the genomic backbone. Phenotypic properties of these viruses were determined by plaque assays and virus adsorption and penetration assays in cultured cells.
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Metal hypersensitivity in patient with posterior lumbar spine fusion: a case report and its literature review.
BMC Musculoskelet Disord
PUBLISHED: 04-21-2014
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Metal hypersensitivity, mostly documented in prosthesis implantation, is a rare complication after arthroplasty. Such cases become rarer and more difficult to diagnose when it comes to lumbar surgery.
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Selective and simultaneous determination of trace bisphenol A and tebuconazole in vegetable and juice samples by membrane-based molecularly imprinted solid-phase extraction and HPLC.
Food Chem
PUBLISHED: 04-20-2014
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Nanofibrous molecularly imprinted membranes (nano-MIMs) with multi-analyte selectivity were prepared by encapsulating two types of molecularly imprinted polymer nanoparticles (MIP-NPs) into electrospun polyvinyl alcohol nanofibers. The obtained nano-MIMs maintained high molecular selectivity offered by each of the MIP-NPs. Nano-MIM embedding BPA-imprinted nanoparticles and TBZ-imprinted nanoparticles together showed the highest binding selectivity for acid bisphenol A (BPA) and basic tebuconazole (TBZ). This nano-MIM was used as affinity material of membrane-based molecularly imprinted solid-phase extraction (m-MISPE) to extract trace BPA and TBZ in vegetables and juices simultaneously. The recoveries of BPA and TBZ from different samples were higher than 70.33% with RSDs lower than 9.57%. m-MISPE gave better HPLC separation efficiencies and higher recoveries than conventional SPE based on C18/SCX. Multi-analyte selective m-MISPE combined with HPLC realized selective and simultaneous determination of several trace analytes with opposite charges/polarities in different food samples.
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The effect of substrate concentration fluctuation on the performance of high-rate denitrifying reactor.
Bioresour. Technol.
PUBLISHED: 04-17-2014
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A high-rate denitrifying process is sensitive to the operation conditions and the substrate concentration fluctuation can lead to the deterioration or even collapse of process performance. The results of this study showed that the effect of substrate concentration fluctuation on the high-rate denitrification process was related to the substrate concentration and shock duration. The effect of substrate concentration was greater than that of shock duration and nitrate conversion was more sensitive than methanol conversion. The response of denitrification performance was related to the loading saturation (maximum loading rate/loading capacity ratio). When the loading saturation was lower than 32%, the high-rate denitrification process could stay in pseudo steady state, otherwise it would easily lose stability. The response of denitrification performance could be divided into three periods. The performance deterioration of high-rate denitrifying process could be attributed to the overload trigger and the toxicity of free nitrous acid.
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Genomic analysis and expression investigation of caleosin gene family in Arabidopsis.
Biochem. Biophys. Res. Commun.
PUBLISHED: 04-16-2014
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Caleosin is a common lipid-droplet surface protein, which has the ability to bind calcium. Arabidopsis (Arabidopsis thaliana) is considered a model organism in plant researches. Although there are growing researches about caleosin in the past few years, a systemic analysis of caleosins in Arabidopsis is still scarce. In this study, a comprehensive investigation of caleosins in Arabidopsis was performed by bioinformatics methods. Firstly, eight caleosins in Arabidopsis are divided into two types, L-caleosin and H-caleosin, according to their molecular weights, and these two types of caleosin have many differences in characteristics. Secondly, phylogenetic tree result indicates that L-caleosin may evolve from H-caleosin. Thirdly, duplication pattern analysis shows that segmental and tandem duplication are main reasons for Arabidopsis caleosin expansion with the equal part. Fourthly, the expression profiles of caleosins are also investigated in silico in different organs and under various stresses and hormones. In addition, based on promoter analysis, caleosin may be involved in calcium signal transduction and lipid accumulation. Thus, the classification and expression analysis of caleosin genes in Arabidopsis provide facilities to the research of phylogeny and functions in this gene family.
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A physics-based temperature model for ultrasonic vibration-assisted pelleting of cellulosic biomass.
Ultrasonics
PUBLISHED: 03-06-2014
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Temperature in ultrasonic vibration-assisted (UV-A) pelleting of cellulosic biomass has a significant impact on pellet quality. However, there are no reports on temperature models for UV-A pelleting of cellulosic biomass. The development of a physics-based temperature model can help to explain experimentally determined relations between UV-A pelleting process variables and temperature, and provide guidelines to optimize these process variables in order to produce pellets of good quality. This paper presents such a model for UV-A pelleting of cellulosic biomass. Development of the model is described first. Then temperature distribution is investigated using the model, and temperature difference between the top and the bottom surfaces of a pellet is explained. Based on this model, relations between process variables (ultrasonic power and pelleting duration) and temperature are predicted. Experiments were conducted for model verification, and the results agreed well with model predictions.
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Probing the transmembrane structure and dynamics of microsomal NADPH-cytochrome P450 oxidoreductase by solid-state NMR.
Biophys. J.
PUBLISHED: 03-02-2014
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NADPH-cytochrome P450 oxidoreductase (CYPOR) is an essential redox partner of the cytochrome P450 (cyt P450) superfamily of metabolic enzymes. In the endoplasmic reticulum of liver cells, such enzymes metabolize ~75% of the pharmaceuticals in use today. It is known that the transmembrane domain of CYPOR plays a crucial role in aiding the formation of a complex between CYPOR and cyt P450. Here we present the transmembrane structure, topology, and dynamics of the FMN binding domain of CYPOR in a native membrane-like environment. Our solid-state NMR results reveal that the N-terminal transmembrane domain of CYPOR adopts an ?-helical conformation in the lipid membrane environment. Most notably, we also show that the transmembrane helix is tilted ~13° from the lipid bilayer normal, and exhibits motions on a submillisecond timescale including rotational diffusion of the whole helix and fluctuation of the helical director axis. The approaches and the information reported in this study would enable further investigations on the structure and dynamics of the full-length NADPH-cytochrome P450 oxidoreductase and its interaction with other membrane proteins in a membrane environment.
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An unexpected particle oscillation for electrophoresis in viscoelastic fluids through a microchannel constriction.
Biomicrofluidics
PUBLISHED: 03-01-2014
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Electrophoresis plays an important role in many applications, which, however, has so far been extensively studied in Newtonian fluids only. This work presents the first experimental investigation of particle electrophoresis in viscoelastic polyethylene oxide (PEO) solutions through a microchannel constriction under pure DC electric fields. An oscillatory particle motion is observed in the constriction region, which is distinctly different from the particle behavior in a polymer-free Newtonian fluid. This stream-wise particle oscillation continues until a sufficient number of particles form a chain to pass through the constriction completely. It is speculated that such an unexpected particle oscillating phenomenon is a consequence of the competition between electrokinetic force and viscoelastic force induced in the constriction. The electric field magnitude, particle size, and PEO concentration are all found to positively affect this viscoelasticity-related particle oscillation due to their respective influences on the two forces.
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Transcriptional Pause Release Is a Rate-Limiting Step for Somatic Cell Reprogramming.
Cell Stem Cell
PUBLISHED: 02-18-2014
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Reactivation of the pluripotency network during somatic cell reprogramming by exogenous transcription factors involves chromatin remodeling and the recruitment of RNA polymerase II (Pol II) to target loci. Here, we report that Pol II is engaged at pluripotency promoters in reprogramming but remains paused and inefficiently released. We also show that bromodomain-containing protein 4 (BRD4) stimulates productive transcriptional elongation of pluripotency genes by dissociating the pause release factor P-TEFb from an inactive complex containing HEXIM1. Consequently, BRD4 overexpression enhances reprogramming efficiency and HEXIM1 suppresses it, whereas Brd4 and Hexim1 knockdown do the opposite. We further demonstrate that the reprogramming factor KLF4 helps recruit P-TEFb to pluripotency promoters. Our work thus provides a mechanism for explaining the reactivation of pluripotency genes in reprogramming and unveils an unanticipated role for KLF4 in transcriptional pause release.
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Effect of model dissolved organic matter coating on sorption of phenanthrene by TiO2 nanoparticles.
Environ. Pollut.
PUBLISHED: 02-16-2014
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Dissolved organic matter (DOM) may alter the sorption of hydrophobic organic contaminants (HOC) to metal oxide nanoparticles (NPs), but the role of DOM and NP types is poorly understood. Here, phenanthrene sorption was quantified on four types of nano-TiO2 (three rutile, one anatase), and a bulk, raw TiO2 powder. Prior to the sorption experiments, these nanoparticles were coated using four different organic materials: Lignin (LIG), tannic acid (TAN), Congo red (CON), and capsorubin (CAP). Lignin, tannic acid, congo red and capsorubin coating substantially enhanced phenanthrene sorption to various TiO2 particles. After coating with a specific DOM, Kd values by the DOM-coated TiO2 particles on percent organic carbon content and surface area (SA) basis (Koc/SA) generally followed the order: TiO2 NPs with hydrophobic surfaces > bulk TiO2 particles > other TiO2 NPs. Different Koc/SA values of various DOM-TiO2 complexes resulted from distinct conformation of the coated DOM and aggregation.
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Distribution of ?-asarone in brain following three different routes of administration in rats.
Eur J Pharm Sci
PUBLISHED: 02-14-2014
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The goal of the present paper is to compare the distributions of ?-asarone administered to rats through three different routes: oral, intravenous and intranasal. The concentrations of ?-asarone in seven distinct brain regions, the olfactory bulb, cerebellum, hypothalamus, frontal cortex, striatum, hippocampus and medulla/pons as well as in plasma and cerebrospinal fluid (CSF), were determined by HPLC. The quantities of ?-asarone accumulated in liver were measured to determine whether ?-asarone could generate hepatotoxicity when administered via the three different routes. The results indicated that ?-asarone could be absorbed via two different routes into the brain, after intranasal administration of dry powders. In the systemic route, ?-asarone immediately entered the brain through the blood-brain barrier (BBB) after uptake into the circulatory system. In the olfactory bulb route, ?-asarone traveled from the olfactory epithelium in the nasal cavity straight into brain tissue via the olfactory bulb. Furthermore, intranasal administration of ?-asarone as a dry powder can ensure quick absorption and avoid excessive concentrations in the blood and liver, while achieving concentrations in the brain comparable to those attained by intravenous and oral administration routes.
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The association of single nucleotide polymorphism of the Fyn gene with sporadic Alzheimer's disease in the Chinese Han population.
Neurosci. Lett.
PUBLISHED: 02-03-2014
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Recent studies suggested genetic factors contribute to the pathogenesis of sporadic Alzheimer's disease (sAD). Fibroblast Yes related novel (Fyn), a tau kinase, has been reported to be associated with aberrant phosphorylated tau and neurofibrillary tangles formation. Fyn gene may be a potential candidate gene for AD. To investigate the association of the polymorphisms in Fyn gene with the susceptibility to sAD, we conducted a case-control study in a Chinese Han cohort including 200 sAD patients and 243 control participants. Four single nucleotide polymorphisms (SNPs) (rs111787668, rs1057979, rs6916861 and rs12910) within the promoter region of Fyn gene and one (rs7768046) in intron were selected and genotyped with a polymerase chain reaction-ligase detection reaction (PCR-LDR) method. Logistic regression under four genetic models was used to analyze the association between target SNPs and the risk of sAD. After adjusting for age, sex and APOE ?4 status, no association was revealed between these SNPs or the haplotypes containing four SNPs and the risk of sAD (P>0.05). The SNPs in the selected regions of the Fyn gene are unlikely to confer the susceptibility of sAD in the Chinese Han population. Further studies with a larger sample size and different ethnic populations are needed to reveal the role of Fyn gene in the pathogenesis of sAD.
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Manipulation of monoubiquitin improves chilling tolerance in transgenic tobacco (Nicotiana tabacum).
Plant Physiol. Biochem.
PUBLISHED: 01-22-2014
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Ubiquitin (Ub) is a multifunctional protein that mainly functions to tag proteins for selective degradation by the 26S proteasome. We cloned an Ub gene TaUb2 from wheat (Triticum aestivum L.) previously. To study the function of TaUB2 in chilling stress, sense and antisense Ub transgenic tobacco plants (Nicotiana tabacum L.), as well as wild type (WT) and vector control ?-glucuronidase (T-GUS) plants, were used. Under stress, leaf wilting in sense plants was significantly less than in controls, but more severe in antisense plants. Meanwhile, the net photosynthetic rate (Pn) and the maximal photochemical efficiency of PSII (Fv/Fm) in sense plants were greater than controls, but lower in antisense plants during chilling stress and recovery. Less wilting in sense plants resulted from improved water status, which may be related to the accumulation of proline and solute sugar. Furthermore, as indicated by electrolyte leakage, membrane damage under stress was less in sense plants and more severe in antisense plants than controls. Consistent with electrolyte leakage, the malondialdehyde (MDA) content was less in sense plants, but more in antisense plants compared to controls. Meanwhile, the less accumulation of reactive oxygen species (ROS) and the greater antioxidant enzyme activity in sense plants implied the improved antioxidant competence by the overexpression of monoubiquitin gene Ta-Ub2 from wheat. We suggest that overexpressing Ub is a useful strategy to promote chilling tolerance. The improvement of ROS scavenging may be an important mechanism underlying the role of Ub in promoting plants tolerant to chilling stress.
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Constraint on selenium bioavailability caused by its geochemical behavior in typical Kaschin-Beck disease areas in Aba, Sichuan Province of China.
Sci. Total Environ.
PUBLISHED: 01-19-2014
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Kaschin-Beck disease (KBD), an endemic osteoarthropathy, is distributed in the low-selenium (Se)-belt that stretches from northeast to southwest China. However, very few studies have investigated the relationship between low bioavailabitity of Se and KBD. The present study examined the behavior of Se and other elements in areas with varying levels of KBD prevalence using pedological and geochemical methods. Rhizosphere soil samples obtained from the KBD-stricken Aba area were classified into Ustic Isohumisols (J2), Udic Luvisols (L4), Stagnic Gleysols (I2), and Cryic Cambisols (M1) and the integrated constraints on selenium bioavailability in these soils were analyzed. We found that Se concentration in soil profiles from a typical KBD area ranged between 0.08 ?g · g(-1) and 0.215 ?g · g(-1), indicating absent and marginal bioavailability, respectively. This suggested that low Se bioavailability may be a feature that soils inherit from their Se-deficient parent materials. Moreover, the soil types examined showed different geochemical behaviors such as eluviation for soluble Se(VI), migration of Se(IV) for its adsorption on clay and sesquioxide, and extreme redox conditions. In conclusion, a higher level of Se bioavailability in environment might be related to a lower risk of KBD, and our results offer a foundation for scientific theory on ecological geochemistry and improve our understanding of KBD.
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Cell-penetrating Peptide-mediated topical delivery of biomacromolecular drugs.
Curr Pharm Biotechnol
PUBLISHED: 01-16-2014
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Biomacromolecules play an important role in the treatment of many diseases, but their topical application has been limited by their poor cell membrane permeability. Cell-penetrating peptides (CPPs) have been investigated over the past few decades as a potential strategy to overcome this challenge. CPPs can effectively mediate the cellular uptake of poorly internalized biomacromolecules without unfavorable side effects and have therefore attracted considerable interest as a viable alternative to existing parenteral therapies involving biomacromolecules. In this review, we will highlight the application of CPPs to the non-invasive delivery of biomacromolecules, with a focus on percutaneous and nasal absorption of biomacromolecules administered using CPPs.
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Increased expression of prothymosin-?, independently or combined with TP53, correlates with poor prognosis in colorectal cancer.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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Human prothymosin-? (PTMA) plays an important role in tumorigenesis, and its overexpression triggers a TP53 response. In this study, we identified that PTMA expression was up-regulated at both the transcriptional and translational level in tumor tissue compared to that in adjacent normal tissue. PTMA overexpression was significantly associated with the depth of tumor invasion, lymph node metastasis (LNM), distant metastasis, advanced AJCC stage, and tumor differentiation. There was also a significant association between PTMA over-expression and mutant TP53 expression (r=0.515, P < 0.001). Survival analysis revealed that the disease-free survival (DFS) and overall survival (OS) rates were significantly lower among patients with PTMA- and TP53-positive tumors. Hence, PTMA might play an important role in the progression of CRC, and the assessment of both PTMA and mutant TP53 expression can help predict colon cancer prognosis.
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Enhanced photocatalytic activity for H2 evolution under irradiation of UV-vis light by Au-modified nitrogen-doped TiO2.
PLoS ONE
PUBLISHED: 01-01-2014
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Photocatalytic water splitting for hydrogen evolution is a potential way to solve many energy and environmental issues. Developing visible-light-active photocatalysts to efficiently utilize sunlight and finding proper ways to improve photocatalytic activity for H2 evolution have always been hot topics for research. This study attempts to expand the use of sunlight and to enhance the photocatalytic activity of TiO2 by N doping and Au loading.
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Variants identified by hepatocellular carcinoma and chronic hepatitis B virus infection susceptibility GWAS associated with survival in HBV-related hepatocellular carcinoma.
PLoS ONE
PUBLISHED: 01-01-2014
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Recent genome-wide association studies (GWAS) have identified several common susceptibility loci associated with the risk of hepatocellular carcinoma (HCC) or chronic hepatitis B infection (CHB). However, the relationship between these genetic variants and survival of patients with hepatitis B virus (HBV)-related HCC is still unknown. In this study, 22 single nucleotide polymorphisms (SNPs) were genotyped among 330 HBV-related HCC patients using the MassARRAY system from Sequenom. Cox proportional hazards regression was used to examine the effects of genotype on survival time under an additive model with age, sex, smoking status and clinical stage as covariates. We identified four SNPs on 6p21 (rs1419881 T>C, rs7453920 G>A,rs3997872 G>A and rs7768538 T>C), and two SNPs on 8p12 (rs2275959 C>T and rs7821974 C>T) significantly associated with survival time of HBV-related HCC patients. Our results suggest that HCC or CHB susceptibility loci might also affect the prognosis of patients with HBV-related HCC.
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Distinct risk profiles for human infections with the Influenza A(H7N9) virus among rural and urban residents: Zhejiang Province, China, 2013.
PLoS ONE
PUBLISHED: 01-01-2014
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To identify the risk factors and source of infection leading to human infections with the Influenza A(H7N9) virus in urban and rural areas.
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[Research advances on anaerobic ferrous-oxidizing microorganisms].
Ying Yong Sheng Tai Xue Bao
PUBLISHED: 12-31-2013
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Anaerobic ferrous-oxidizing microorganisms (AFOM) are one of the important discoveries in microbiology, geology and environmental science. The study of AFOM is of significance to make clear the banded iron formations (BIFs), promote the biogeochemical cycles of iron, nitrogen and carbon, enrich the microbiological content, develop new biotechnologies for anaerobic iron oxidation, and explore the ancient earth environment and extraterrestrial life. This paper summarized the research advances on AFOM, introduced the habitats of AFOM, discussed the biodiversity and the nutritive and metabolic characteristics of AFOM, and assessed the potential functions of AFOM. An outlook was made on the future researches of new species AFOM, their microbial metabolism mechanisms, and their development and applications.
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Chinese childrens predictions of emotion in rule situations.
Psychol Rep
PUBLISHED: 12-18-2013
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This study investigated childrens predictions in contexts in which desires conflict with forbidden rules. Forty-eight children participated: 4-year-olds, 5-year-olds, and 7-year-olds, with 8 boys and 8 girls in each group. The children listened to stories and were asked to predict behaviors and emotions. The story portrayed one child who wanted to engage in an activity in a certain domain (personal or prudential), but an authority (adult or peer) prohibited him/her from doing so. Only 5- and 7-year-olds predicted more positive emotions for breaking the rule and more negative emotions for complying with the rule in the personal domain than in the prudential domain. The results indicated that older children differentiated the personal domain from the prudential domain. Older children can differentiate adult authority from peer authority. When rules were given by an adult authority, 7-year-olds predicted more positive emotions for transgression and more negative emotions for compliance than when the rules were given by peer authority. Four- and 5-year-olds predictions did not differ when rules were stated by either of the two authorities.
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Magnetic Superatoms in VLin (n = 1-13) Clusters: A First-Principles Prediction.
J Phys Chem A
PUBLISHED: 11-21-2013
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We demonstrated a first-principles investigation to search for magnetic superatoms in the vanadium-doped lithium clusters VLin (n = 1-13). The stabilities of VLin clusters were determined through geometrical and electronic optimizations. It is found that the growth pattern of VLin in 3-space follows adding a Li atom capped on VLin-1 clusters. All doped clusters show larger relative binding energies compared with pure Lin+1 partners and display tunable magnetic properties. When n = 8-13, the VLin clusters adopt a cage-like structure with an endohedral V atom and are identified as superatoms with their magnetic moments successively decreasing from 5 to 0 ?B. The isolated VLi8 superatom is emphasized due to its robust magnetic moment as well as high structural and chemical stability analogue of a single Mn(2+) ion. Molecular orbitals analysis shows that VLi8 has an electronic configuration of 1S(2)1P(6)1D(5), exhibiting Hunds filling rule of maximizing the spin-like atoms. Electronic shell structures of 1S(2) and 1P(6) are virtually unchanged in Li9 cluster as the V atom substitutes for the embedded Li atom, indicating that the electron-shell-closing model is valid for explaining its structures and stabilities. The results show that the tailored magnetic building blocks for nanomaterials can be formed by seeding magnetic dopants into alkali metal cluster cages.
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Facilitation and correlation of flow in metallic supercooled liquid.
J Chem Phys
PUBLISHED: 11-05-2013
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Elucidation of the flow mechanism of the supercooled liquid near the glass transition temperature Tg is crucial for understanding the nature of glass transition. Dynamic facilitation between adjacent flow events in the supercooled liquid is believed to be crucial in the process of glass transition. In this work, it is shown that shear dilatation-based dynamic facilitation plays an important role in the supercooled liquid state of Zr58.5Cu15.6Al10.3Ni12.8Nb2.8, as revealed by the observed strain rate softening in the stress-strain curves above Tg = 684 K. Interestingly, along with strain rate softening, damped oscillations in the stress-strain curve emerge below 713 K, suggesting large-scale correlation between flow events as temperature approaches Tg. Such oscillations are absent above 713 K although strain rate softening remains even at 733 K. Analysis indicates that facilitation and correlation are both crucial for the flow of metallic supercooled liquid approaching Tg.
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Association between the polymorphism of estrogen receptor alpha and Alzheimers disease in Chinese population.
Clin. Lab.
PUBLISHED: 10-19-2013
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To investigate the possible association between the polymorphism of estrogen receptor alpha (ERalpha) and Alzheimers disease (AD) in Chinese population.
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Floatation of granular sludge and its mechanism: A key approach for high-rate denitrifying reactor.
Bioresour. Technol.
PUBLISHED: 10-06-2013
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A high-rate denitrifying automatic circulate (DAC) reactor has been developed recently, and it is promising to become an alternative in nitrogen removal from wastewaters. However, the performance of DAC reactor was disturbed by the floatation of granular sludge at high-loads. The results showed that: the floatation of granular sludge led to a serious biomass washout and a sharp decrease of biomass concentration. The floatation of granular sludge was ascribed to a low sludge density originated from the holdup of gaseous products. The average density and average gas holdup ratio of floated granular sludge were 913kgm(-3) and 11.8% (by volume), respectively. The floatation of granular sludge could disappear by releasing gas when sludge was in the state of elastic expansion, but it would become worse by holding gas when it entered the plastic expansion state. The plastic expansion of granules was significantly correlated with the less content of extracellular polymeric substances.
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Bioinspired greigite magnetic nanocrystals: chemical synthesis and biomedicine applications.
Sci Rep
PUBLISHED: 10-02-2013
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Large scale greigite with uniform dimensions has stimulated significant demands for applications such as hyperthermia, photovoltaics, medicine and cell separation, etc. However, the inhomogeneity and hydrophobicity for most of the as prepared greigite crystals has limited their applications in biomedicine. Herein, we report a green chemical method utilizing ?-cyclodextrin (?-CD) and polyethylene glycol (PEG) to synthesize bioinspired greigite (Fe?S?) magnetic nanocrystals (GMNCs) with similar structure and magnetic property of magnetosome in a large scale. ?-CD and PEG is responsible to control the crystal phase and morphology, as well as to bound onto the surface of nanocrystals and form polymer layers. The GMNCs exhibit a transverse relaxivity of 94.8?mM?¹ s?¹ which is as high as iron oxide nanocrystals, and an entrapment efficiency of 58.7% for magnetic guided delivery of chemotherapeutic drug doxorubicin. Moreover, enhanced chemotherapeutic treatment of mice tumor was obtained via intravenous injection of doxorubicin loaded GMNCs.
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A randomized, placebo-controlled study of the pharmacokinetics, pharmacodynamics, and tolerability of the oral JAK2 inhibitor fedratinib (SAR302503) in healthy volunteers.
J Clin Pharmacol
PUBLISHED: 09-30-2013
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Fedratinib (SAR302503/TG101348) is a Janus kinase 2 (JAK2)-selective inhibitor in clinical development for the treatment of myelofibrosis. In this randomized, placebo-controlled, Phase 1 study, the pharmacokinetics, pharmacodynamics and tolerability of ascending single doses of fedratinib (10-680?mg) were assessed in healthy male subjects. Fedratinib was rapidly absorbed, with peak plasma concentration observed approximately 3 hours after dosing. The mean terminal half-life of fedratinib was approximately 67 hours, which was unaffected by dose. Fedratinib exposure increased in a greater than dose-proportional manner. Suppression of signal transducer and activator of transcription 3 (STAT3) phosphorylation, indicative of JAK2 inhibition, was observed at 3 hours post-dose for subjects in the 300, 500, and 680?mg groups, with the level of suppression increasing with dose. The relationship between fedratinib exposure and suppression of STAT3 phosphorylation was described using an inhibitory effect sigmoid Emax model, with an EC50 of 1,210?ng/mL in healthy subjects. The most common adverse events were mild gastrointestinal toxicities.
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[Expression and clinical significance of Nusap1 in hepatical carcinoma].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 09-28-2013
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To investigate the expression and clinical significance of Nusap1 in hepatical carcinoma.
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Spatiotemporal cortical activation underlies the Müller-Lyer illusion: an event-related potentials study.
Neuroreport
PUBLISHED: 09-26-2013
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Event-related brain potentials (ERPs) were used to examine the electrophysiological correlates of the visual illusion effect in the Müller-Lyer illusion tasks. The participants were presented with the context of a horizontal line with two symmetric inward-pointing arrowheads or outward-pointing arrowheads, and then, they were asked to indicate whether they perceived an increase or a decrease in the line length. The behavioral results showed that there were significant differences among the four types of tasks, which meant that participants could understand different mean illusion magnitudes. The ERP results showed that both the illusion-45 and the illusion-135 elicited a more negative ERP deflection (N180-280) than did the illusion-225 and illusion-315 between 180 and 280 ms. In addition, the strong illusion stimuli elicited a more positive ERP deflection (P280-450) than did the weak illusion stimuli between 280 and 450 ms after the onset of the stimuli. Dipole source analysis of the difference wave (illusion-135-illusion-225) indicated that one generator localized in the left lateral occipital cortex and the difference wave (illusion-45-illusion-135) indicated that one generator localized in the left lingual gyrus. Our results led us to conclude that the ERP deflection in the different illusory strength might be related to the theory of attention resource distribution or because of the inverse optics problem. Then, the early visual areas lateral occipital cortex and the lingual gyrus near to the visual cortex could contribute to integrated processing in the illusory contours and top-down control processing because of the visual experiences.
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Preparation and pH controlled release of polyelectrolyte complex of poly(l-malic acid-co-d,l-lactic acid) and chitosan.
Colloids Surf B Biointerfaces
PUBLISHED: 09-24-2013
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The copolymer of poly(l-malic acid-co-d,l-lactic acid) (PML) was synthesized through a direct polycondensation of l-malic acid (MA) and d,l-lactic acid (LA). Then, a new polyelectrolyte complex (PEC) based on the complexation between the copolymer (PML) and chitosan (CS) was prepared. The PEC formed stable nano particles in aqueous solutions with pH 3-5, and the nano particles had the diameters in a range of 316-590nm (varied with the components of PML and CS). Doxorubicin (DOX) as a model drug was loaded on the nano particles through the physical adsorption and complexation, and part of DOX formed the secondary particles by self-aggregation. The high drug loading efficiency (16.5%) and the sustained release patterns in acidic media were observed, and the release accelerated in alkaline solutions. The nano particles could be potentially applied as pH sensitive drug vehicles for controlled release.
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Characteristics of self-alkalization in high-rate denitrifying automatic circulation (DAC) reactor fed with methanol and sodium acetate.
Bioresour. Technol.
PUBLISHED: 09-23-2013
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Denitrification is a self-alkalization process. In this experiment, the characteristics of self-alkalization in high-rate heterotrophic denitrifying automatic circulation (DAC) reactor fed with methanol and sodium acetate were investigated, respectively. The results showed that, (1) The self-alkalization of high-rate denitrifying reactors was remarkably strong both with methanol and sodium acetate as carbon sources, while the effluent pH was much lower than the stoichiometric values and the malfunction from self-alkalization of denitrification was far less serious than expected. (2) The self-adaptation of the reactors was attributed to the neutralization of carbon dioxide (oxidization product of organic matter) and the self-adaptation of denitrifying sludge. The formation and discharge of calcium carbonate precipitates gave rise to lower effluent pH and alkalinity than the stoichiometric values.
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Lithium attenuates IFN-? production and antiviral response via inhibition of TANK-binding kinase 1 kinase activity.
J. Immunol.
PUBLISHED: 09-16-2013
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Lithium salt is a widely used glycogen synthase kinase-3? inhibitor and effective drug for the treatment of psychiatric diseases. However, the effects of lithium in innate immune responses, especially in cellular antiviral responses, are unknown. In this study, we show that lithium chloride attenuates LPS-, polyinosinic-polycytidylic acid-, and Sendai virus-induced IFN-? production and IFN regulatory factor 3 activation in macrophages in a glycogen synthase kinase-3?-independent manner. The ability of the lithium to inhibit IFN-? production was confirmed in vivo, as mice treated with lithium chloride exhibited decreased levels of IFN-? upon Sendai virus infection. In vitro kinase assay demonstrates that lithium suppresses TANK-binding kinase 1 kinase activity. Consistently, lithium significantly enhanced the replication of vesicular stomatitis virus in vitro and in vivo. Severe infiltration of monocytes and tissue damage were observed in the lungs of control mice, compared with lithium-treated mice after virus infection. Our findings suggest lithium as an inhibitor of TANK-binding kinase 1 and potential target for the intervention of diseases with uncontrolled IFN-? production. Furthermore, lithium attenuates host defense to virus infection and may cause severely adverse effects in clinical applications.
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Cross-sectional study of indices of dynamic components of ambulatory blood pressure and cardiac damage in elderly male patients with essential hypertension.
Aging Clin Exp Res
PUBLISHED: 09-15-2013
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Blood pressure control is closely related to target organ damage in elderly patients with hypertension. The aim of this study was to determine the relationship between ambulatory blood pressure monitoring (ABPM) indices and cardiac damage in elderly male patients with treated essential hypertension (EH).
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[Adsorption of Cd2+ ions in aqueous by diamine-modified ordered mesoporous SBA-15 particles].
Huan Jing Ke Xue
PUBLISHED: 09-14-2013
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Highly ordered channel structure SBA-15 was widely concerned as new adsorbents in environmental protection, in order to increase its heavy metal ions adsorption ability from aqueous solution, the diamine -modified porous silicate SBA-15 was synthesized by a hydrothermal grafting method and characterized by TEM, X-ray diffraction, FTIR and N2 adsorption-desorption. The SBA-15 and modified SBA-15 samples were used as sorbents to adsorb Cd(II) ions from aqueous solution. The effect of experimental parameters, such as pH, contact time, sorbent dosage and temperature were examined, and the maximum adsorption amount was also calculated. The results showed that under same conditions, the Cd(II) removal rate was higher for 2N-SBA-15 than that of the unmodified SBA-15. The adsorption process was controlled by system pH. The highest removal rate could reached about 95% after pH was higher than 4. Adsorption equilibrium was reached within 30 minutes,and more than 95% Cd2+ was adsorbed when 7.5-20 mg sorbent was added into 100 mL solution contained 25 mg x L(-1) Cd2+. The adsorption capacity increased from 94.73% to 98.22% with temperature increased from 25 degrees C to 35 degrees C. The Langmuir model can be used to describe adsorption isotherms. The adsorption capacity of Cd2+ was 0.9 mmol x g(-1) which is comparable to the adsorption capacity of various adsorbents reported in the literature, and 0.1 mol x L(-1) HCl could remove nearly 93% Cd2+ from 2N-SBA-15 particles. Based on the thermodynamic, pH, XPS and Zeta potential analysis results in this study, it could be concluded that the adsorption process was an endothermic and spontaneous reaction which contained physical adsorption, ion exchange and chelating reaction etc. The study indicated that the diamine -modified ordered mesoporous material SBA-15 is a potential sorbent which could be used for the aqueous Cd2+ removal.
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Radical-Radical Interactions among Oxidized Guanine Bases Including Guanine Radical Cation and Dehydrogenated Guanine Radicals.
J Phys Chem B
PUBLISHED: 09-06-2013
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We present here a theoretical investigation of the structural and electronic properties of di-ionized GG base pairs (G(•+)G(•+),G(-H1)(•)G(•+), and G(-H1)(•)G(-H1)(•)) consisting of the guanine cation radical (G(•+)) and/or dehydrogenated guanine radical (G(-H1)(•)) using density functional theory calculations. Different coupling modes (Watson-Crick/WC, Hoogsteen/Hoog, and minor groove/min hydrogen bonding, and ?-? stacking modes) are considered. We infer that a series of G(•+)G(•+) complexes can be formed by the high-energy radiation. On the basis of density functional theory and complete active space self-consistent (CASSCF) calculations, we reveal that in the H-bonded and N-N cross-linked modes, (G(•+)G(•+))WC, (G(-H1)(•)G(-H1)(•))WC, (G(-H1)(•)G(-H1)(•))minI, and (G(-H1)(•)G(-H1)(•))minIII have the triplet ground states; (G(•+)G(•+))HoogI, (G(-H1)(•)G(•+))WC, (G(-H1)(•)G(•+))HoogI, (G(-H1)(•)G(•+))minI, (G(-H1)(•)G(•+))minII, and (G(-H1)(•)G(-H1)(•))minII possess open-shell broken-symmetry diradical-characterized singlet ground states; and (G(•+)G(•+))HoogII, (G(•+)G(•+))minI, (G(•+)G(•+))minII, (G(•+)G(•+))minIII, (G(•+)G(•+))HoHo, (G(-H1)(•)G(•+))minIII, (G(-H1)(•)G(•+))HoHo, and (G(-H1)(•)G(-H1)(•))HoHo are the closed-shell systems. For these H-bonded diradical complexes, the magnetic interactions are weak, especially in the diradical G(•+)G(•+) series and G(-H1)(•)G(-H1)(•) series. The magnetic coupling interactions of the diradical systems are controlled by intermolecular interactions (H-bond, electrostatic repulsion, and radical coupling). The radical-radical interaction in the ?-? stacked di-ionized GG base pairs ((G(•+)G(•+))??, (G(-H1)(•)G(•+))??, and (G(-H1)(•)G(-H1)(•))??) are also considered, and the magnetic coupling interactions in these ?-? stacked base pairs are large. This is the first theoretical prediction that some di-ionized GG base pairs possess diradical characters with variable degrees of ferromagnetic and antiferromagnetic characteristics, depending on the dehydrogenation characters of the bases and their interaction modes. Hopefully, this work provides some helpful information for the understanding of different structures and properties of the di-ionized GG base pairs.
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