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Find video protocols related to scientific articles indexed in Pubmed.
Trisulfur Radical Anion as the Key Intermediate for the Synthesis of Thiophene via the Interaction between Elemental Sulfur and NaOtBu.
Org. Lett.
PUBLISHED: 11-20-2014
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A facile base-promoted sulfur-centered radical generation mode and a single-step protocol for the synthesis of thiophene derivatives using 1,3-diynes via the interaction between elemental sulfur and NaOtBu has been reported. EPR experiments revealed that the trisulfur radical anion acts as a key intermediate of this process. A plausible mechanism has been proposed.
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Long-Term Colorectal-Cancer Mortality after Adenoma Removal.
N. Engl. J. Med.
PUBLISHED: 11-20-2014
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To the Editor: The study of colorectal-cancer mortality by Løberg et al. (Aug. 28 issue)(1) provides no data on the quality of the colonoscopies performed. This limitation outweighs the merits of the large population size and prolonged follow-up in this study, and it precludes meaningful inferences regarding the protective effect of colonoscopy against colorectal cancer. We think the results are best explained by polyps left behind or incompletely removed because of the use of a suboptimal technique.(2),(3) The timing of colonoscopy may explain the modest mortality benefit among patients with low-risk adenomas versus no benefit among patients with multiple . . .
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Cu(II)/Cu(I)-Synergistic Cooperation to Lead the Alkyne C-H Activation.
J. Am. Chem. Soc.
PUBLISHED: 11-11-2014
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An efficient alkyne C-H activation procedure has been well studied which indicated that a Cu(II)/Cu(I) synergistic co-operation might be involved. In situ Raman spectroscopy was engaged to study kinetic behavior, drawing the conclusion that Cu(II) didn't participate in the rate determining step. IR and X-ray absorption spectroscopy evidence were provided for structural information, indicating that Cu(II) alone couldn't accelerate the reduction procedure by simply coordinating with C-C triple bond to activate the terminal alkynes; meanwhile, X-band EPR spectra and solubility showed that Cu(I) and Cu(II) could affect the complication environment of each other. A distinctive Cu(I)-Cu(II) synergistic cooperation intermediate was proposed for the putative mechanism.
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Aggregation Properties of the Small Nuclear Ribonucleoprotein U1-70K in Alzheimer Disease.
J. Biol. Chem.
PUBLISHED: 10-31-2014
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Recent evidence indicates that U1-70K and other U1 small nuclear ribonucleoproteins (snRNPs) are sarkosyl-insoluble and associate with tau neurofibrillary tangles selectively in Alzheimer disease (AD). Currently, the mechanisms underlying the conversion of soluble nuclear U1 snRNPs into insoluble cytoplasmic aggregates remain elusive. Based on the biochemical and subcellular distribution properties of U1-70K in AD we hypothesized that aggregated U1-70K itself or other biopolymers (e.g. proteins or nucleic acids) interact with and sequester natively folded soluble U1-70K into insoluble aggregates. Here we demonstrate that total homogenates from AD brain induce soluble U1-70K from control brain or recombinant U1-70K to become sarkosyl-insoluble. This effect was not dependent on RNA, and did not correlate with detergent-insoluble tau levels as AD homogenates with reduced levels of these components were still capable of inducing U1-70K aggregation. In contrast, proteinase K-treated AD homogenates and sarkosyl-soluble AD fractions were unable to induce U1-70K aggregation, indicating that aggregated proteins in AD brain are responsible for inducing soluble U1-70K aggregation. It was determined that the C-terminus of U1-70K, that harbors two disordered low-complexity (LC) domains, is necessary for U1-70K aggregation. Moreover, both LC1 and LC2 domains were sufficient for aggregation. Finally, protein cross-linking and mass spectrometry studies demonstrated that a U1-70K fragment harboring the LC1 domain directly interacts with aggregated U1-70K in AD brain. Our results support a hypothesis that aberrant forms of U1-70K in AD can directly sequester soluble forms of U1-70K into insoluble aggregates.
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Trans-Golgi Network-Located AP1 Gamma Adaptins Mediate Dileucine Motif-Directed Vacuolar Targeting in Arabidopsis.
Plant Cell
PUBLISHED: 10-30-2014
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Membrane proteins on the tonoplast are indispensible for vacuolar functions in plants. However, how these proteins are transported to the vacuole and how they become separated from plasma membrane proteins remain largely unknown. In this study, we used Arabidopsis thaliana vacuolar ion transporter1 (VIT1) as a reporter to study the mechanisms of tonoplast targeting. We showed that VIT1 reached the tonoplast through a pathway involving the endoplasmic reticulum (ER), Golgi, trans-Golgi network (TGN), prevacuolar compartment, and tonoplast. VIT1 contains a putative N-terminal dihydrophobic type ER export signal, and its N terminus has a conserved dileucine motif (EKQTLL), which is responsible for tonoplast targeting. In vitro peptide binding assays with synthetic VIT1 N terminus identified adaptor protein complex-1 (AP1) subunits that interacted with the dileucine motif. A deficiency of AP1 gamma adaptins in Arabidopsis cells caused relocation of tonoplast proteins containing the dileucine motif, such as VIT1 and inositol transporter1, to the plasma membrane. The dileucine motif also effectively rerouted the plasma membrane protein SCAMP1 to the tonoplast. Together with subcellular localization studies showing that AP1 gamma adaptins localize to the TGN, we propose that the AP1 complex on the TGN mediates tonoplast targeting of membrane proteins with the dileucine motif.
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HLA-DQA1 and PLCG2 Are Candidate Risk Loci for Childhood-Onset Steroid-Sensitive Nephrotic Syndrome.
J. Am. Soc. Nephrol.
PUBLISHED: 10-29-2014
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Steroid-sensitive nephrotic syndrome (SSNS) accounts for >80% of cases of nephrotic syndrome in childhood. However, the etiology and pathogenesis of SSNS remain obscure. Hypothesizing that coding variation may underlie SSNS risk, we conducted an exome array association study of SSNS. We enrolled a discovery set of 363 persons (214 South Asian children with SSNS and 149 controls) and genotyped them using the Illumina HumanExome Beadchip. Four common single nucleotide polymorphisms (SNPs) in HLA-DQA1 and HLA-DQB1 (rs1129740, rs9273349, rs1071630, and rs1140343) were significantly associated with SSNS at or near the Bonferroni-adjusted P value for the number of single variants that were tested (odds ratio, 2.11; 95% confidence interval, 1.56 to 2.86; P=1.68×10(-6) (Fisher exact test). Two of these SNPs-the missense variants C34Y (rs1129740) and F41S (rs1071630) in HLA-DQA1-were replicated in an independent cohort of children of white European ancestry with SSNS (100 cases and ?589 controls; P=1.42×10(-17)). In the rare variant gene set-based analysis, the best signal was found in PLCG2 (P=7.825×10(-5)). In conclusion, this exome array study identified HLA-DQA1 and PLCG2 missense coding variants as candidate loci for SSNS. The finding of a MHC class II locus underlying SSNS risk suggests a major role for immune response in the pathogenesis of SSNS.
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I2-catalyzed oxidative C(sp(3))-H/S-H coupling: utilizing alkanes and mercaptans as the nucleophiles.
Chem. Commun. (Camb.)
PUBLISHED: 10-10-2014
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By using alkanes and mercaptans as the nucleophiles with di-tert-butyl peroxide (DTBP) as the oxidant, I2-catalyzed oxidative C(sp(3))-H/S-H coupling was achieved. This protocol provides a novel process to construct C(sp(3))-S bonds from commercially available hydrocarbons and mercaptans.
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IP-10 and MIG are compartmentalized at the site of disease during pleural and meningeal tuberculosis and are decreased after anti-tuberculosis treatment.
Clin. Vaccine Immunol.
PUBLISHED: 10-03-2014
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The diagnosis of active tuberculosis (TB) disease remains a challenge especially in high-burden settings. Cytokines and chemokines are important in the pathogenesis of TB. Here, we investigate the usefulness of circulating and compartmentalized cytokines/chemokines for diagnosis of TB. The levels of multiple cytokines/chemokines in plasma, pleural fluid (PF) and cerebrospinal fluid (CSF) were determined by Luminex liquid array-based multiplexed immunoassays. Three of 26 cytokines/chemokines in plasma were significantly different between TB and latent tuberculosis infection (LTBI). Among them, IP-10 and MIG had the highest diagnostic values, with an area under the receiver operating characteristic curve (ROC AUC) of 0.92 for IP-10 and 0.86 for MIG to distinguish TB from LTBI. However, IP-10 and MIG in plasma were not different between TB and non-TB lung disease. In contrast, compartmentalized IP-10 and MIG in the PF and CSF showed promising diagnostic values in discriminating TB and non-TB pleural effusion (AUC=0.87 for IP-10, AUC=0.93 for MIG), as well as TB meningitis and non-TB meningitis (AUC=0.9 for IP-10, AUC=0.95 for MIG). A longitudinal study showed that the plasma levels of IP-10, MIG, G-CSF and IFN-Y decreased, while the levels of MCP-1/CCL2 and Eotaxin-1/CCL11 increased, after successful treatment of TB. Our findings provided a practical methodology for discriminating active TB from LTBI by sequential IGRAs and plasma IP-10 test, while increased IP-10 and MIG at the site of infection (PF or CSF) can be used a marker for distinguishing pleural effusion and meningitis caused by TB from those by non-TB.
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Copper-Catalyzed Radical Carbooxygenation: Alkylation and Alkoxylation of Styrenes.
Chem Asian J
PUBLISHED: 09-19-2014
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A simple copper-catalyzed direct radical carbooxygenation of styrenes is developed utilizing alkyl bromides as radical resources. This catalytic radical difunctionalization accomplishes both alkylation and alkoxylation of styrenes in one pot. A broad range of styrenes and alcohols are well tolerated in this transformation. The EPR experiment shows that alkyl halides could oxidize Cu(I) to Cu(II) in this transformation.
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[Expression of Annexin A1 in paclitaxel-resistant ovarian carcinoma and its clinical significance].
Zhong Nan Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 09-10-2014
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To investigate the correlation of Annexin A1 (ANXA1) expression with paclitaxel response and clinicopathological features of ovarian carcinoma.
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Efficient synthesis of 1,2,3-triazoles by copper-mediated c?n and n?n bond formation starting from N-tosylhydrazones and amines.
Chemistry
PUBLISHED: 09-03-2014
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An effective copper-mediated synthesis of 1,5-dialkyl-4-aryl-1,2,3-triazoles and 1,4-dialkyl-5-aryl-1,2,3-triazoles has been achieved by the use of different N-tosylhydrazones and alkyl amines. The scope of the substrates could be extended from anilines to aliphatic amines when 30?mol?% amino acid is added into the reaction mixture. This methodology exhibits many notable features, such as broad substrates scope, high efficiency, and good regioselectivity. Preliminary mechanistic studies indicated that the reaction probably proceeded through a 1-tosyl-2-vinyldiazene intermediate and subsequent aza-Michael addition and N?N bond formation process.
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C6 ceramide sensitizes pemetrexed-induced apoptosis and cytotoxicity in osteosarcoma cells.
Biochem. Biophys. Res. Commun.
PUBLISHED: 08-22-2014
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Chemotherapy has significantly improved the prognosis of high-grade osteosarcoma (OS), but over 30% of OS patients can still not be cured. Pemetrexed, the newly-developed anti-folate chemotherapy drug, exerted lower efficacy against OS cells. Here, we aimed to increase pemetrexed efficiency, and found that the cell-permeable short-chain ceramide (C6) significantly enhanced pemetrexed-induced viability reduction and death in cultured OS cell lines (U2OS and MG-63). Pemetrexed induced moderate apoptosis in OS cells, which was dramatically augmented by C6 ceramide. The apoptosis inhibitor z-VAD-fmk largely inhibited C6 ceramide plus pemetrexed-induced cytotoxicity and apoptosis in OS cells. By using pharmacological and siRNA-knockdown strategies, we showed that Akt-mammalian TOR (mTOR) over-activation was an important pemetrexed resistance factor in OS cells, and C6 ceramide-mediated pemetrexed sensitization effect was mediated, at least in part, by Akt-mTOR inhibition. Finally, we found that Akt-S6 Kinase 1 (S6K1, an indicator of mTOR activation) was over-activated in human OS tissues. On the other hand, the osteoblastic MC3T3-E1 cells, which expressed lower Akt-S6K1 phosphorylation, were resistant to pemetrexed and/or C6 ceramide. Together, we conclude that C6 ceramide sensitizes pemetrexed-induced apoptosis and cytotoxicity in OS cells probably through in-activation of Akt-mTOR signaling.
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Analysis of prevacuolar compartment-mediated vacuolar proteins transport.
Methods Mol. Biol.
PUBLISHED: 08-14-2014
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Transient expression using protoplasts is a quick and powerful tool for studying protein trafficking and subcellular localization in plant cells. Prevacuolar compartments (PVCs) or multivesicular bodies (MVBs) are intermediate compartments that mediate protein transport between late Golgi or trans-Golgi network (TGN) and vacuole. Both wortmannin treatment and ARA7(Q69L) expression can induce PVC homotypic fusion and PVC enlargement in plant cells. Here, we describe detailed protocols to use transient expression of protoplasts derived from Arabidopsis suspension culture cells for studying protein trafficking and localization. Using three GFP-tagged vacuolar cargo proteins and RFP-tagged PVC membrane marker as examples, we illustrate the major tools and methods, including wortmannin treatment, ARA7(Q69L) expression and immunoblot analysis, to analyze PVC-mediated vacuolar protein transport in plant cells.
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Extremely low-frequency electromagnetic fields cause G1 phase arrest through the activation of the ATM-Chk2-p21 pathway.
PLoS ONE
PUBLISHED: 08-11-2014
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In daily life, humans are exposed to the extremely low-frequency electromagnetic fields (ELF-EMFs) generated by electric appliances, and public concern is increasing regarding the biological effects of such exposure. Numerous studies have yielded inconsistent results regarding the biological effects of ELF-EMF exposure. Here we show that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, inhibiting cell proliferation. To present well-founded results, we comprehensively evaluated the biological effects of ELF-EMFs at the transcriptional, protein, and cellular levels. Human HaCaT cells from an immortalized epidermal keratinocyte cell line were exposed to a 1.5 mT, 60 Hz ELF-EMF for 144 h. The ELF-EMF could cause G1 arrest and decrease colony formation. Protein expression experiments revealed that ELF-EMFs induced the activation of the ATM/Chk2 signaling cascades. In addition, the p21 protein, a regulator of cell cycle progression at G1 and G2/M, exhibited a higher level of expression in exposed HaCaT cells compared with the expression of sham-exposed cells. The ELF-EMF-induced G1 arrest was diminished when the CHK2 gene expression (which encodes checkpoint kinase 2; Chk2) was suppressed by specific small interfering RNA (siRNA). These findings indicate that ELF-EMFs activate the ATM-Chk2-p21 pathway in HaCaT cells, resulting in cell cycle arrest at the G1 phase. Based on the precise control of the ELF-EMF exposure and rigorous sham-exposure experiments, all transcriptional, protein, and cellular level experiments consistently supported the conclusion. This is the first study to confirm that a specific pathway is triggered by ELF-EMF exposure.
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Use of Hematopoietic Growth Factors in Elderly Lung Cancer Patients Receiving Chemotherapy: A SEER-Medicare-based Study.
Am. J. Clin. Oncol.
PUBLISHED: 07-29-2014
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Hematopoietic growth factors (HGFs) are essential for successful completion of chemotherapy in lung cancer patients. However, because of their adverse effects, clinical guidelines recommend their use in only selective clinical scenarios. This study, for the first time, explores patient characteristics and temporal trends associated with HGF utilization among elderly lung cancer patients receiving chemotherapy.
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Copper-catalysed direct radical alkenylation of alkyl bromides.
Org. Biomol. Chem.
PUBLISHED: 07-29-2014
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A copper-catalysed direct radical alkenylation of various benzyl bromides and ?-carbonyl alkyl bromides has been developed. Compared with the recent radical alkenylations which mostly focused on secondary or tertiary alkyl halides, this transformation shows good reactivity to primary alkyl halides and tertiary, secondary alkyl halides were also tolerated. The key initiation step of this transformation is a copper-induced single-electron reduction of C-Br bonds to generate alkyl radical species.
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Carbon-centered radical addition to o?c of amides or esters as a route to c?o bond formations.
Chemistry
PUBLISHED: 07-27-2014
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Among various types of radical reactions, the addition of carbon radicals to unsaturated bonds is a powerful tool for constructing new chemical bonds, in which the typical applied unsaturated substrates include alkenes, alkynes and imines. Carbonyl is perhaps the most common unsaturated group in nature. This work demonstrates a novel C?O bond formation through carbon-centered radical addition to the carbonyl oxygen of amide or ester, in which amide and ester groups are easily activated through the radical process. EPR spectroscopy and radical clock experiments support the radical process for this transformation, and density functional theory (DFT) calculations support the possibility of carbon-centered radical addition to the carbonyl oxygen of amides or esters.
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3D imaging of transition metals in the zebrafish embryo by X-ray fluorescence microtomography.
Metallomics
PUBLISHED: 07-05-2014
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Synchrotron X-ray fluorescence (SXRF) microtomography has emerged as a powerful technique for the 3D visualization of the elemental distribution in biological samples. The mechanical stability, both of the instrument and the specimen, is paramount when acquiring tomographic projection series. By combining the progressive lowering of temperature method (PLT) with femtosecond laser sectioning, we were able to embed, excise, and preserve a zebrafish embryo at 24 hours post fertilization in an X-ray compatible, transparent resin for tomographic elemental imaging. Based on a data set comprised of 60 projections, acquired with a step size of 2 ?m during 100 hours of beam time, we reconstructed the 3D distribution of zinc, iron, and copper using the iterative maximum likelihood expectation maximization (MLEM) reconstruction algorithm. The volumetric elemental maps, which entail over 124 million individual voxels for each transition metal, revealed distinct elemental distributions that could be correlated with characteristic anatomical features at this stage of embryonic development.
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Modified THz electro-optic sampling for high optical modulation depth, large dynamical range, and low background noises.
Opt Lett
PUBLISHED: 07-01-2014
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We present a modified THz electro-optic sampling method to combine the advantages of its two traditional counterparts at near 0° and 45° optical biases: excellent ability to cancel the background noises, high optical modulation, and large dynamical range. The first advantage results from the method's symmetrical layout to get dynamical noise cancellation. By setting the static birefringent phases of the two balanced beams with a pair of opposite numbers, our setup can record THz waveforms without distortion with its maximal modulation depth, thus optimal signal-to-noise ratio (SNR). The setting also releases the linearity of the measured signal from the static birefringence, thus enlarging greatly the linear dynamical range. For a given THz field, the recorded SNR with our setup, without a lock-in, is more than 10 times higher than that with the "crossed and balanced" design [IEEE Trans. Microwave Theory Tech. 47, 2644 (1999)].
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Increased vesicular monoamine transporter enhances dopamine release and opposes Parkinson disease-related neurodegeneration in vivo.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 06-16-2014
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Disruption of neurotransmitter vesicle dynamics (transport, capacity, release) has been implicated in a variety of neurodegenerative and neuropsychiatric conditions. Here, we report a novel mouse model of enhanced vesicular function via bacterial artificial chromosome (BAC)-mediated overexpression of the vesicular monoamine transporter 2 (VMAT2; Slc18a2). A twofold increase in vesicular transport enhances the vesicular capacity for dopamine (56%), dopamine vesicle volume (33%), and basal tissue dopamine levels (21%) in the mouse striatum. The elevated vesicular capacity leads to an increase in stimulated dopamine release (84%) and extracellular dopamine levels (44%). VMAT2-overexpressing mice show improved outcomes on anxiety and depressive-like behaviors and increased basal locomotor activity (41%). Finally, these mice exhibit significant protection from neurotoxic insult by the dopaminergic toxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), as measured by reduced dopamine terminal damage and substantia nigra pars compacta cell loss. The increased release of dopamine and neuroprotection from MPTP toxicity in the VMAT2-overexpressing mice suggest that interventions aimed at enhancing vesicular capacity may be of therapeutic benefit in Parkinson disease.
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Copper-catalysed oxidative Csp(3)-H methylenation to terminal olefins using DMF.
Chem. Commun. (Camb.)
PUBLISHED: 06-05-2014
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A copper-catalysed direct oxidative Csp(3)-H methylenation to terminal olefins using DMF as one carbon source was developed. In this reaction, various functional groups were well tolerated, thus providing a simple way to construct arylvinylketones and arylvinylpyridines. The preliminary mechanistic investigations revealed that CH2 was from DMF (N-CH3).
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Colorectal cancer prevention by an optimized colonoscopy protocol in routine practice.
Int. J. Cancer
PUBLISHED: 06-02-2014
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We conducted a retrospective cohort study to investigate the colorectal cancer (CRC) incidence and mortality prevention achievable in clinical practice with an optimized colonoscopy protocol targeting near-complete polyp clearance. The protocol consisted of: (i) telephonic reinforcement of bowel preparation instructions; (ii) active inspection for polyps throughout insertion and circumferential withdrawal; and (iii) timely updating of the protocol and documentation to incorporate the latest guidelines. Of 17,312 patients provided screening colonoscopies by 59 endoscopists in South Carolina, USA from September 2001 through December 2008, 997 were excluded using accepted exclusion criteria. Data on 16,315 patients were merged with the South Carolina Central Cancer Registry and Vital Records Registry data from January 1996 to December 2009 to identify incident CRC cases and deaths, incident lung cancers and brain cancer deaths (comparison control cancers). The standardized incidence ratios (SIR) and standardized mortality ratios (SMR) relative to South Carolina and US SEER-18 population rates were calculated. Over 78,375 person-years of observation, 18 patients developed CRC versus 104.11 expected for an SIR of 0.17, or 83% CRC protection, the rates being 68% and 91%, respectively among the adenoma- and adenoma-free subgroups (all p < 0.001). Restricting the cohort to ensure minimum 5-year follow-up (mean follow-up 6.64 years) did not change the results. The CRC mortality reduction was 89% (p < 0.001; four CRC deaths vs. 35.95 expected). The lung cancer SIR was 0.96 (p?=?0.67), and brain cancer SMR was 0.92 (p?=?0.35). Over 80% reduction in CRC incidence and mortality is achievable in routine practice by implementing key colonoscopy principles targeting near-complete polyp clearance.
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Exploring personalized searches using tag-based user profiles and resource profiles in folksonomy.
Neural Netw
PUBLISHED: 05-25-2014
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With the increase in resource-sharing websites such as YouTube and Flickr, many shared resources have arisen on the Web. Personalized searches have become more important and challenging since users demand higher retrieval quality. To achieve this goal, personalized searches need to take users' personalized profiles and information needs into consideration. Collaborative tagging (also known as folksonomy) systems allow users to annotate resources with their own tags, which provides a simple but powerful way for organizing, retrieving and sharing different types of social resources. In this article, we examine the limitations of previous tag-based personalized searches. To handle these limitations, we propose a new method to model user profiles and resource profiles in collaborative tagging systems. We use a normalized term frequency to indicate the preference degree of a user on a tag. A novel search method using such profiles of users and resources is proposed to facilitate the desired personalization in resource searches. In our framework, instead of the keyword matching or similarity measurement used in previous works, the relevance measurement between a resource and a user query (termed the query relevance) is treated as a fuzzy satisfaction problem of a user's query requirements. We implement a prototype system called the Folksonomy-based Multimedia Retrieval System (FMRS). Experiments using the FMRS data set and the MovieLens data set show that our proposed method outperforms baseline methods.
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Engineering single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets for high performance lithium ion batteries.
Nanoscale
PUBLISHED: 05-16-2014
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Well shaped single crystalline Mn3O4 nano-octahedra with exposed highly active {011} facets at different particle sizes have been synthesized and used as anode materials for lithium ion batteries. The electrochemical results show that the smallest sized Mn3O4 nano-octahedra show the best cycling performance with a high initial charge capacity of 907 mA h g(-1) and a 50th charge capacity of 500 mA h g(-1) at a current density of 50 mA g(-1) and the best rate capability with a charge capacity of 350 mA h g(-1) when cycled at 500 mA g(-1). In particular, the nano-octahedra samples demonstrate a much better electrochemical performance in comparison with irregular shaped Mn3O4 nanoparticles. The best electrochemical properties of the smallest Mn3O4 nano-octahedra are ascribed to the lower charge transfer resistance due to the exposed highly active {011} facets, which can facilitate the conversion reaction of Mn3O4 and Li owing to the alternating Mn and O atom layers, resulting in easy formation and decomposition of the amorphous Li2O and the multi-electron reaction. On the other hand, the best electrochemical properties of the smallest Mn3O4 nano-octahedra can also be attributed to the smallest size resulting in the highest specific surface area, which provides maximum contact with the electrolyte and facilitates the rapid Li-ion diffusion at the electrode/electrolyte interface and fast lithium-ion transportation within the particles. The synergy of the exposed {011} facets and the smallest size (and/or the highest surface area) led to the best performance for the Mn3O4 nano-octahedra. Furthermore, HRTEM observations verify the oxidation of MnO to Mn3O4 during the charging process and confirm that the Mn3O4 octahedral structure can still be partly maintained after 50 discharge-charge cycles. The high Li-ion storage capacity and excellent cycling performance suggest that Mn3O4 nano-octahedra with exposed highly active {011} facets could be excellent anode materials for high-performance lithium-ion batteries.
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The Arabidopsis Endosomal Sorting Complex Required for Transport III Regulates Internal Vesicle Formation of the Prevacuolar Compartment and Is Required for Plant Development.
Plant Physiol.
PUBLISHED: 05-08-2014
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We have established an efficient transient expression system with several vacuolar reporters to study the roles of endosomal sorting complex required for transport (ESCRT)-III subunits in regulating the formation of intraluminal vesicles of prevacuolar compartments (PVCs)/multivesicular bodies (MVBs) in plant cells. By measuring the distributions of reporters on/within the membrane of PVC/MVB or tonoplast, we have identified dominant negative mutants of ESCRT-III subunits that affect membrane protein degradation from both secretory and endocytic pathways. In addition, induced expression of these mutants resulted in reduction in luminal vesicles of PVC/MVB, along with increased detection of membrane-attaching vesicles inside the PVC/MVB. Transgenic Arabidopsis (Arabidopsis thaliana) plants with induced expression of ESCRT-III dominant negative mutants also displayed severe cotyledon developmental defects with reduced cell size, loss of the central vacuole, and abnormal chloroplast development in mesophyll cells, pointing out an essential role of the ESCRT-III complex in postembryonic development in plants. Finally, membrane dissociation of ESCRT-III components is important for their biological functions and is regulated by direct interaction among Vacuolar Protein Sorting-Associated Protein20-1 (VPS20.1), Sucrose Nonfermenting7-1, VPS2.1, and the adenosine triphosphatase VPS4/SUPPRESSOR OF K(+) TRANSPORT GROWTH DEFECT1.
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Design, synthesis and in vitro and in vivo antitumour activity of 3-benzylideneindolin-2-one derivatives, a novel class of small-molecule inhibitors of the MDM2-p53 interaction.
Eur J Med Chem
PUBLISHED: 05-05-2014
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A novel class of small-molecule inhibitors of MDM2-p53 interaction with a (E)-3-benzylideneindolin-2-one scaffold was identified using an integrated virtual screening strategy that combined both pharmacophore- and structure-based approaches. The hit optimisation identified several compounds with more potent activity than the hit compound and the positive drug nutlin-3a, especially compound 1b, which exhibited both the highest binding affinity to MDM2 (Ki = 0.093 ?M) and the most potent antiproliferative activity against HCT116 (wild type p53) cells (GI50 = 13.42 ?M). Additionally, 1b dose-dependently inhibited tumour growth in BALB/c mice bearing CT26 colon carcinoma, with no visible sign of toxicity. In summary, compound 1b represents a novel and promising lead structure for the development of anticancer drugs as MDM2-p53 interaction disruptors.
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Community-aware user profile enrichment in folksonomy.
Neural Netw
PUBLISHED: 05-04-2014
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In the era of big data, collaborative tagging (a.k.a. folksonomy) systems have proliferated as a consequence of the growth of Web 2.0 communities. Constructing user profiles from folksonomy systems is useful for many applications such as personalized search and recommender systems. The identification of latent user communities is one way to better understand and meet user needs. The behavior of users is highly influenced by the behavior of their neighbors or community members, and this can be utilized in constructing user profiles. However, conventional user profiling techniques often encounter data sparsity problems as data from a single user is insufficient to build a powerful profile. Hence, in this paper we propose a method of enriching user profiles based on latent user communities in folksonomy data. Specifically, the proposed approach contains four sub-processes: (i) tag-based user profiles are extracted from a folksonomy tripartite graph; (ii) a multi-faceted folksonomy graph is constructed by integrating tag and image affinity subgraphs with the folksonomy tripartite graph; (iii) random walk distance is used to unify various relationships and measure user similarities; (iv) a novel prototype-based clustering method based on user similarities is used to identify user communities, which are further used to enrich the extracted user profiles. To evaluate the proposed method, we conducted experiments using a public dataset, the results of which show that our approach outperforms previous ones in user profile enrichment.
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Structural analysis of respiratory syncytial virus reveals the position of M2-1 between the matrix protein and the ribonucleoprotein complex.
J. Virol.
PUBLISHED: 04-23-2014
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Respiratory syncytial virus (RSV), a member of the Paramyxoviridae family of nonsegmented, negative-sense, single-stranded RNA genome viruses, is a leading cause of lower respiratory tract infections in infants, young children, and the elderly or immunocompromised. There are many open questions regarding the processes that regulate human RSV (hRSV) assembly and budding. Here, using cryo-electron tomography, we identified virus particles that were spherical, filamentous, and asymmetric in structure, all within the same virus preparation. The three particle morphologies maintained a similar organization of the surface glycoproteins, matrix protein (M), M2-1, and the ribonucleoprotein (RNP). RNP filaments were traced in three dimensions (3D), and their total length was calculated. The measurements revealed the inclusion of multiple full-length genome copies per particle. RNP was associated with the membrane whenever the M layer was present. The amount of M coverage ranged from 24% to 86% in the different morphologies. Using fluorescence light microscopy (fLM), direct stochastic optical reconstruction microscopy (dSTORM), and a proximity ligation assay (PLA), we provide evidence illustrating that M2-1 is located between RNP and M in isolated viral particles. In addition, regular spacing of the M2-1 densities was resolved when hRSV viruses were imaged using Zernike phase contrast (ZPC) cryo-electron tomography. Our studies provide a more complete characterization of the hRSV virion structure and substantiation that M and M2-1 regulate virus organization.
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Immunoglobulin molecules detection with nanopore sensors fabricated from glass tubes.
J Nanosci Nanotechnol
PUBLISHED: 04-18-2014
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Nanopores are increasingly utilized as tools for single molecule detection in biotechnology. Here, we report an improved fabrication process to make solid-state nanopores from glass tubes with the help of paraffin. Based on the physical footprint of the phase change of the paraffin, nanocavity is formed in the broken terminal after thermally compressing and pulling the glass capillary. Nanopores with the minimum diameter of 50 nm are fabricated. Different immunoglobulin molecules including IgG, IgA, IgM mixed in a 10 mM KCl solution are used to test the sensing capabilities of the glass-nanopore sensor. Various modulated ionic current modes were observed while the the three type immunoglobulin molecules translocate the nanopore because the molecules had different size and structure. Based on the difference in the duration time and amplitude of the transient electrical pulse signals, we are able to discriminate the three immunoglobulin molecules.
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Coupling of ultrafast LC with mass spectrometry by DESI.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 03-25-2014
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Recently we reported a desorption electrospray ionization (DESI) interface to combine liquid chromatography (LC) with mass spectrometry (MS) using a new LC eluent splitting strategy through a tiny orifice on LC capillary tube [J. Am. Soc. Mass Spectrom. 25, 286 (2014)]. The interface introduces negligible dead volume and back pressure, thereby allowing "near real-time" MS detection, fast LC elution, and online MS-directed purification. This study further evaluates the LC/DESI-MS performance with focus of using ultra-fast LC. Using a monolithic C18 column, metabolites in urine can be separated within 1.6 min and can be online collected for subsequent structure elucidation (e.g., by NMR, UV, IR) in a recovery yield up to 99%. Using a spray solvent with alkaline pH, negative ions could be directly generated for acidic analytes (e.g., ibuprofen) in acidic LC eluent by DESI, offering a novel protocol to realize "wrong-way around" ionization for LC/MS analysis. In addition, DESI-MS is found to be compatible with ultra-performance liquid chromatography (UPLC) for the first time.
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Engineered insulin secretion from neuroendocrine cells isolated from human thyroid.
World J Surg
PUBLISHED: 02-20-2014
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Insulin-secreting beta-like cells are vulnerable to diabetic autoimmunity. We hypothesized that human thyroid neuroendocrine (NE) cells could be engineered to secrete human insulin, be glucose-responsive, and avoid autoimmunity.
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Aggregates of small nuclear ribonucleic acids (snRNAs) in Alzheimer's disease.
Brain Pathol.
PUBLISHED: 02-13-2014
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We recently discovered that protein components of the ribonucleic acid (RNA) spliceosome form cytoplasmic aggregates in Alzheimer's disease (AD) brain, resulting in widespread changes in RNA splicing. However, the involvement of small nuclear RNAs (snRNAs), also key components of the spliceosome complex, in the pathology of AD remains unknown. Using immunohistochemical staining of post-mortem human brain and spinal cord, we identified cytoplasmic tangle-shaped aggregates of snRNA in both sporadic and familial AD cases but not in aged controls or other neurodegenerative disorders. Immunofluorescence using antibodies reactive with the 2,2,7-trimethylguanosine cap of snRNAs and transmission electron microscopy demonstrated snRNA localization with tau and paired helical filaments, the main component of neurofibrillary tangles. Quantitative real-time polymerase chain reaction (PCR) showed U1 snRNA accumulation in the insoluble fraction of AD brains whereas other U snRNAs were not enriched. In combination with our previous results, these findings demonstrate that aggregates of U1 snRNA and U1 small nuclear ribonucleoproteins represent a new pathological hallmark of AD.
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Imaging the condensation and evaporation of molecularly thin ethanol films with surface forces apparatus.
Rev Sci Instrum
PUBLISHED: 02-13-2014
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A new method for imaging condensation and evaporation of molecularly thin ethanol films is reported. It is found that the first adsorbed layer of ethanol film on mica surface behaves as solid like structure that cannot flow freely. With the increase of exposure time, more ethanol molecules condense over the mica surface in the saturated ethanol vapor condition. The first layer of adsorbed ethanol film is about 3.8 Å thick measured from the surface forces apparatus, which is believed to be the average diameter of ethanol molecules while they are confined in between two atomically smooth mica surfaces.
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U1 small nuclear ribonucleoproteins (snRNPs) aggregate in Alzheimer's disease due to autosomal dominant genetic mutations and trisomy 21.
Mol Neurodegener
PUBLISHED: 01-31-2014
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We recently identified U1 small nuclear ribonucleoprotein (snRNP) tangle-like aggregates and RNA splicing abnormalities in sporadic Alzheimer's disease (AD). However little is known about snRNP biology in early onset AD due to autosomal dominant genetic mutations or trisomy 21 in Down syndrome. Therefore we investigated snRNP biochemical and pathologic features in these disorders.
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Facile synthesis of hierarchical and porous V2O5 microspheres as cathode materials for lithium ion batteries.
J Colloid Interface Sci
PUBLISHED: 01-28-2014
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Hierarchical and porous V2O5 microspheres have been fabricated by a refluxing approach followed by annealing in air. The resulting porous V2O5 microspheres typically have diameters of 3-6 ?m and are constructed of intertwined laminar nanocrystals or crosslinked nanobricks. It is found that the vanadyl glycolates rinsed with water have pronounced pore structures than that rinsed with ethanol alone. In addition, the configuration of the vanadyl glycolates microspheres can be tuned during the refluxing along with stirring. The possible formation processes of the vanadyl glycolates and V2O5 products have been discussed based on the experimental data. Electrochemical tests indicate that the hierarchical and porous V2O5 microspheres exhibit relatively high and stable Li(+) storage properties. The porous V2O5 microspheres assembled by intertwined nanoparticles maintain reversible Li(+) storage capacities of 102 and 80 mAh g(-1), respectively; whilst the porous V2O5 microspheres assembled by crosslinked nanobricks maintain reversible Li(+) storage capacities of 100 and 85 mAh g(-1) over 100 cycles at current rates of 0.5 and 1 C, respectively. The superior Li(+) storage performance of the hierarchical and porous V2O5 microspheres could mainly be ascribed to the improved electrode/electrolyte interface, reduced Li(+) diffusion paths, and relieved volume variation during lithiation and delithiation processes.
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Retention mechanisms for ER and Golgi membrane proteins.
Trends Plant Sci.
PUBLISHED: 01-23-2014
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Unless there are mechanisms to selectively retain membrane proteins in the endoplasmic reticulum (ER) or in the Golgi apparatus, they automatically proceed downstream to the plasma or vacuole membranes. Two types of coat protein complex I (COPI)-interacting motifs in the cytosolic tails of membrane proteins seem to facilitate membrane retention in the early secretory pathway of plants: a dilysine (KKXX) motif (which is typical of p24 proteins) for the ER and a KXE/D motif (which occurs in the Arabidopsis endomembrane protein EMP12) for the Golgi apparatus. The KXE/D motif is highly conserved in all eukaryotic EMPs and is additionally present in hundreds of other proteins of unknown subcellular localization and function. This novel signal may represent a new general mechanism for Golgi targeting and the retention of polytopic integral membrane proteins.
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Development of a miniature dielectric barrier discharge-optical emission spectrometric system for bromide and bromate screening in environmental water samples.
Anal. Chim. Acta
PUBLISHED: 01-15-2014
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Dielectric barrier discharge (DBD) at atmospheric pressure provides an efficient radiation source for the excitation of bromine and it is used for the first time for optical emission spectrometric (OES) detection of bromide and bromate. A portable DBD-OES system is developed for screening potential pollution from bromide and bromate in environmental waters. Bromide is on-line oxidized to bromine for in-situ generation of volatile bromine. Meanwhile, a helium stream carries bromine into the DBD micro-plasma for its excitation at a discharging voltage of 3.7 kV and optical emission spectrometric detection with a QE65000 charge-coupled device (CCD) spectrometer in the near-infrared spectral region. Similarly, the quantification of bromate is performed by its pre-reduction into bromide and then oxidized to bromine. The spectral characteristics and configuration of the DBD micro-plasma excitation source in addition to the oxidation vapor generation of bromine have been thoroughly investigated. With a sampling volume of 1 mL, a linear range of 0.05-10.0 mg L(-1) is obtained with a detection limit of 0.014 mg L(-1) by measuring the emission at 827 nm. A precision of 2.3% is achieved at 3 mg L(-1) bromide. The system is validated by bromine detection in certified reference material of laver (GBW10023) at mg L(-1) level, giving rise to satisfactory agreement. In addition, it is further demonstrated by screening trace bromide and bromate as well as spiking recoveries in a series of environmental water samples.
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Synthesis of 6-acyl phenanthridines by oxidative radical decarboxylation-cyclization of ?-oxocarboxylates and isocyanides.
Chem. Commun. (Camb.)
PUBLISHED: 01-14-2014
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A silver catalysed synthesis of 6-acyl phenanthridines by oxidative radical decarboxylation-cyclization of ?-oxocarboxylates and isocyanides was developed. This reaction provided a novel method to realize C1 insertion via a radical process and various functional groups were well-tolerated.
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Facile and fast synthesis of porous TiO2 spheres for use in lithium ion batteries.
J Colloid Interface Sci
PUBLISHED: 01-11-2014
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Porous anatase TiO2 spheres have been synthesized by a microwave-assisted hydrothermal reaction of spherical particle precursors followed by annealing in air. The synthesized TiO2 spheres are formed by interconnected nanocrystals with size of 8.7 nm in average and have grain diameters of 250-400 nm. After annealing at 500°C, the TiO2 samples maintain spherical shape and develop highly mesoporous characteristics with a specific surface area of 151 m(2) g(-1). The TiO2 samples annealed at 750°C consist of larger aggregated particles with diameters of 500-900 nm and still retain mesoporous anatase structure, but with a reduced specific surface area of 25.6 m(2) g(-1). Electrochemical studies reveal that the porous TiO2 spheres annealed at 500°C own very high and stable lithium ion (Li(+)) storage capacities of 207, 184, 166, and 119 mA h g(-1) at 0.5, 1, 2, and 5C (850 mA g(-1)) rates, respectively, owing to their highly porous nanostructures and fine spherical morphology. In contrast, the TiO2 spheres annealed at 700°C exhibit modest electrochemical performance due to their reduced pore structures and larger crystallite size. The prepared porous TiO2 spherical particles show great promise for use as high performance anode materials for lithium ion batteries (LIBs).
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Direct observation of reduction of Cu(II) to Cu(I) by terminal alkynes.
J. Am. Chem. Soc.
PUBLISHED: 01-10-2014
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X-ray absorption spectroscopy and in situ electron paramagnetic resonance evidence were provided for the reduction of Cu(II) to Cu(I) species by alkynes in the presence of tetramethylethylenediamine (TMEDA), in which TMEDA plays dual roles as both ligand and base. The structures of the starting Cu(II) species and the obtained Cu(I) species were determined as (TMEDA)CuCl2 and [(TMEDA)CuCl]2 dimer, respectively.
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Synthesis and broad-spectrum antiviral activity of some novel benzo-heterocyclic amine compounds.
Molecules
PUBLISHED: 01-08-2014
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A series of novel unsaturated five-membered benzo-heterocyclic amine derivatives were synthesized and assayed to determine their in vitro broad-spectrum antiviral activities. The biological results showed that most of our synthesized compounds exhibited potent broad-spectrum antiviral activity. Notably, compounds 3f (IC50=3.21-5.06 ?M) and 3g (IC50=0.71-34.87 ?M) showed potent activity towards both RNA viruses (influenza A, HCV and Cox B3 virus) and a DNA virus (HBV) at low micromolar concentrations. An SAR study showed that electron-withdrawing substituents located on the aromatic or heteroaromatic ring favored antiviral activity towards RNA viruses.
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Distinct Epidermal Keratinocytes Respond to Extremely Low-Frequency Electromagnetic Fields Differently.
PLoS ONE
PUBLISHED: 01-01-2014
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Following an increase in the use of electric appliances that can generate 50 or 60 Hz electromagnetic fields, concerns have intensified regarding the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health. Previous epidemiological studies have suggested the carcinogenic potential of environmental exposure to ELF-EMFs, specifically at 50 or 60 Hz. However, the biological mechanism facilitating the effects of ELF-EMFs remains unclear. Cellular studies have yielded inconsistent results regarding the biological effects of ELF-EMFs. The inconsistent results might have been due to diverse cell types. In our previous study, we indicated that 1.5 mT, 60 Hz ELF-EMFs will cause G1 arrest through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells. The aim of the current study was to investigate whether ELF-EMFs cause similar effects in a distinct epidermal keratinocyte, primary normal human epidermal keratinocytes (NHEK), by using the same ELF-EMF exposure system and experimental design. We observed that ELF-EMFs exerted no effects on cell growth, cell proliferation, cell cycle distribution, and the activation of ATM signaling pathway in NHEK cells. We demonstrated that the 2 epidermal keratinocytes responded to ELF-EMFs differently. To further validate this finding, we simultaneously exposed the NHEK and HaCaT cells to ELF-EMFs in the same incubator for 168 h and observed the cell growths. The simultaneous exposure of the two cell types results showed that the NHEK and HaCaT cells exhibited distinct responses to ELF-EMFs. Thus, we confirmed that the biological effects of ELF-EMFs in epidermal keratinocytes are cell type specific. Our findings may partially explain the inconsistent results of previous studies when comparing results across various experimental models.
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Impaired Autophagy Contributes to Adverse Cardiac Remodeling in Acute Myocardial Infarction.
PLoS ONE
PUBLISHED: 01-01-2014
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Autophagy is activated in ischemic heart diseases, but its dynamics and functional roles remain unclear and controversial. In this study, we investigated the dynamics and role of autophagy and the mechanism(s), if any, during postinfarction cardiac remodeling.
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Identification of under-detected periodicity in time-series microarray data by using empirical mode decomposition.
PLoS ONE
PUBLISHED: 01-01-2014
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Detecting periodicity signals from time-series microarray data is commonly used to facilitate the understanding of the critical roles and underlying mechanisms of regulatory transcriptomes. However, time-series microarray data are noisy. How the temporal data structure affects the performance of periodicity detection has remained elusive. We present a novel method based on empirical mode decomposition (EMD) to examine this effect. We applied EMD to a yeast microarray dataset and extracted a series of intrinsic mode function (IMF) oscillations from the time-series data. Our analysis indicated that many periodically expressed genes might have been under-detected in the original analysis because of interference between decomposed IMF oscillations. By validating a protein complex coexpression analysis, we revealed that 56 genes were newly determined as periodic. We demonstrated that EMD can be used incorporating with existing periodicity detection methods to improve their performance. This approach can be applied to other time-series microarray studies.
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Integrated analysis of differential miRNA and mRNA expression profiles in human radioresistant and radiosensitive nasopharyngeal carcinoma cells.
PLoS ONE
PUBLISHED: 01-01-2014
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The purpose of this study was to identify miRNAs and genes involved in nasopharyngeal carcinoma (NPC) radioresistance, and explore the underlying mechanisms in the development of radioresistance.
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[Activation of NOD2 Signalling Pathway Stimulates the Function of Human Dendritic Cells Loaded with Leukemia Cell Lysates].
Zhongguo Shi Yan Xue Ye Xue Za Zhi
PUBLISHED: 12-28-2013
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The purpose of this study was to explore the effect of NOD2 signalling pathway activated by muramyl dipeptide (MDP) on the immunomodulation effect of human monocyte-derived dendritic cells (DC) loaded with leukemia cell lysates. Peripheral blood mononuclear cells (PBMNC) were isolated by density gradient centrifugation, These cells were cultured with three cytokines for 7 days to induce their maturation. On the 5th day, cells were loaded with leukemia cell HL-60 lysates. NOD2 expression was detected by RT-PCR and Western blot. The phenotype of DC were analyzed by flow cytometry, and ELISA was used to assay levels of IL-12 (p40) . The results showed that MDP could trigger NOD2 mRNA and protein expression in different groups of DC, especially in sensitized DC+MDP group, which was significantly higher than that in the DC+MDP group and sensitized DC without MDP stimulation, the difference was statistically significant (P < 0.05). Besides, the expression of surface molecules(HLA-DR, CD80, CD83, CD86, CD40) in the group of DC loaded with leukemia cell lysate and stimulated by MDP (sensitized DC+MDP) reached the highest level, followed by the group of DC loaded with leukemia cell lysate without MDP and DC only stimulated by MDP, non-treated DC were the lowest(P < 0.05). Similarly, compared with untreated unstimulated DC, after loading with HL-60 lysates or only stimulating with MDP, the secretion of IL-12p40 increased, but IL-12p40 level (573.86 ± 32.09 pg/ml) in DC+MDP group was higher than that in group of sensitized DC (365.03 ± 28.86 pg/ml) (P < 0.05), and it in sensitized DC+MDP group reached the highest(898.30 ± 61.08) pg/ml, compared to other groups(P < 0.05). It is concluded that MDP can significantly enhance the NOD2 mRNA and protein expression in sensitized DC, promote the expression of HLA-DR, synergistic costimulatory molecules and adhesion molecules of DC, at the same time, MDP can increase secretion of inflammatory factors IL-12p40. This study will provide a new ideas for DC application in leukemia immunotherapy.
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Combining Single RNA Sensitive Probes with Subdiffraction-Limited and Live-Cell Imaging Enables the Characterization of Virus Dynamics in Cells.
ACS Nano
PUBLISHED: 12-23-2013
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The creation of fluorescently labeled viruses is currently limited by the length of imaging observation time (e.g., labeling an envelope protein) and the rescue of viral infectivity (e.g., encoding a GFP protein). Using single molecule sensitive RNA hybridization probes delivered to the cytoplasm of infected cells, we were able to isolate individual, infectious, fluorescently labeled human respiratory syncytial virus virions. This was achieved without affecting viral mRNA expression, viral protein expression, or infectivity. Measurements included the characterization of viral proteins and genomic RNA in a single virion using dSTORM, the development of a GFP fusion assay, and the development of a pulse-chase assay for viral RNA production that allowed for the detection of both initial viral RNA and nascent RNA production at designated times postinfection. Live-cell measurements included imaging and characterization of filamentous virion fusion and the quantification of virus replication within the same cell over an eight-hour period. Using probe-labeled viruses, individual viral particles can be characterized at subdiffraction-limited resolution, and viral infections can be quantified in single cells over an entire cycle of replication. The implication of this development is that MTRIP labeling of viral RNA during virus assembly has the potential to become a general methodology for the labeling and study of many important RNA viruses.
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Exo70E2 is essential for exocyst subunit recruitment and for EXPO formation in both plants and animals.
Mol. Biol. Cell
PUBLISHED: 12-04-2013
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In contrast to a single copy of Exo70 in yeast and mammals, the Arabidopsis genome contains 23 paralogs of Exo70 (AtExo70). Using AtExo70E2 and its GFP fusion as probes, we have recently identified a novel double-membrane organelle termed EXPO (exocyst-positive organelle) that mediates an unconventional protein secretion in plant cells. Here we further demonstrate that AtExo70E2 is essential for exocyst subunit recruitment and for EXPO formation in both plants and animals. By performing transient expression in Arabidopsis protoplasts we have established that a number of exocyst subunits (especially the members of the Sec family) are unable to be recruited to EXPO in the absence of AtExo70E2. The paralog AtExo70A1 is unable to substitute for AtExo70E2 in this regard. FRET and BiFC analyses have confirmed the interaction between AtExo70E2 and Sec6 and Sec10. AtExo70E2, but not its yeast counterpart, is also capable of inducing EXPO formation in an animal cell line (HEK293A cells). Electron microscopy confirmed the presence of double membraned EXPO-like structures in HEK293A cells expressing AtExo70E2. Inversely, neither human nor yeast Exo70 homologues are able to cause the formation of EXPO in Arabidopsis protoplasts. These results point to a specific and crucial role for AtExo70E2 in EXPO formation.
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Medication Treatment Complexity and Adherence in Children with CKD.
Clin J Am Soc Nephrol
PUBLISHED: 11-21-2013
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The complexity of CKD management in children is increased by the number of comorbid conditions. This study assessed the prevalence of comorbidities in pediatric CKD and the frequency with which multiple comorbidities present together by assessing prevalent medication use by CKD stage and diagnosis and their association with clinical or sociodemographic factors. The association between number and frequency of dosing of medications prescribed and self-report of nonadherence was also assessed.
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A BAR-Domain Protein SH3P2, Which Binds to Phosphatidylinositol 3-Phosphate and ATG8, Regulates Autophagosome Formation in Arabidopsis.
Plant Cell
PUBLISHED: 11-18-2013
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Autophagy is a well-defined catabolic mechanism whereby cytoplasmic materials are engulfed into a structure termed the autophagosome. In plants, little is known about the underlying mechanism of autophagosome formation. In this study, we report that SH3 DOMAIN-CONTAINING PROTEIN2 (SH3P2), a Bin-Amphiphysin-Rvs domain-containing protein, translocates to the phagophore assembly site/preautophagosome structure (PAS) upon autophagy induction and actively participates in the membrane deformation process. Using the SH3P2-green fluorescent protein fusion as a reporter, we found that the PAS develops from a cup-shaped isolation membranes or endoplasmic reticulum-derived omegasome-like structures. Using an inducible RNA interference (RNAi) approach, we show that RNAi knockdown of SH3P2 is developmentally lethal and significantly suppresses autophagosome formation. An in vitro membrane/lipid binding assay demonstrates that SH3P2 is a membrane-associated protein that binds to phosphatidylinositol 3-phosphate. SH3P2 may facilitate membrane expansion or maturation in coordination with the phosphatidylinositol 3-kinase (PI3K) complex during autophagy, as SH3P2 promotes PI3K foci formation, while PI3K inhibitor treatment inhibits SH3P2 from translocating to autophagosomes. Further interaction analysis shows that SH3P2 associates with the PI3K complex and interacts with ATG8s in Arabidopsis thaliana, whereby SH3P2 may mediate autophagy. Thus, our study has identified SH3P2 as a novel regulator of autophagy and provided a conserved model for autophagosome biogenesis in Arabidopsis.
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[Studies on flash extraction methods of Arnebia euchroma].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 11-09-2013
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The extraction of functional components from radix of Arnebia euchroma was optimized using orthogonal design based on the extraction yields of shikonin, and hydroxyl-naphthoquinone pigments. The data processing was carried out with the multiple guidelines grading method for optimizing the extraction condition. Compared with the traditional method (refluxing and ultrasonic extraction), the flash extraction method was more efficient The optimal conditions were as follows: 95% ethanol extract 3 times with 90 s for each. Under these conditions, the extraction yields of shikonin, and hydroxyl-naphthoquinone pigments were 93.16%, 93.89%, respectively, and the dry extract rate was 5.16%. In conclusion, the result showed that the flash extraction technology was appropriate, stable and feasible.
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False-positive Anti-retinal Antibodies as a Cause of Psychogenic Vision Loss.
Ocul. Immunol. Inflamm.
PUBLISHED: 10-08-2013
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Abstract Purpose: To report a case of psychogenic vision loss caused by false-positive anti-retinal antibody testing. Methods: We describe a case of visual and systemic symptoms following anti-retinal antibody detection. The case was analyzed for clinical presentation, diagnosis, and consequences of false-positive testing. Results: The patient presented with decreased vision without detectable pathology on ophthalmic examination. Tests were ordered in search of a diagnosis, including an antibody test. Following detection of anti-retinal antibodies, the patient developed worsening visual symptoms and systemic manifestations. A repeat antibody test performed at our institution revealed negative results, which, in conjunction with lack of visual field expansion, confirmed our suspicion of psychogenic vision loss. Conclusions: Laboratory screening may be limited by test specificity and can lead to false-positive results, affecting the patient psychologically and clinically. Care must be taken in patients with positive anti-retinal antibodies to ensure the presence of definitive disease before initiation of treatment.
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Visible-Light-Mediated Decarboxylation/Oxidative Amidation of ?-Keto Acids with Amines under Mild Reaction Conditions Using O2.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 10-03-2013
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Photochemistry has ushered in a new era in the development of chemistry, and photoredox catalysis has become a hot topic, especially over the last five years, with the combination of visible-light photoredox catalysis and radical reactions. A novel, simple, and efficient radical oxidative decarboxylative coupling with the assistant of the photocatalyst [Ru(phen)3 ]Cl2 is described. Various functional groups are well-tolerated in this reaction and thus provides a new approach to developing advanced methods for aerobic oxidative decarboxylation. The preliminary mechanistic studies revealed that: 1) an SET process between [Ru(phen)3 ](2+) * and aniline play an important role; 2) O2 activation might be the rate-determining step; and 3) the decarboxylation step is an irreversible and fast process.
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Novel role for the Streptococcus pneumoniae toxin pneumolysin in the assembly of biofilms.
MBio
PUBLISHED: 09-12-2013
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Streptococcus pneumoniae is an important commensal and pathogen responsible for almost a million deaths annually in children under five. The formation of biofilms by S. pneumoniae is important in nasopharyngeal colonization, pneumonia, and otitis media. Pneumolysin (Ply) is a toxin that contributes significantly to the virulence of S. pneumoniae and is an important candidate as a serotype-independent vaccine target. Having previously demonstrated that a luxS knockout mutant was unable to form early biofilms and expressed less ply mRNA than the wild type, we conducted a study to investigate the role of Ply in biofilm formation. We found that Ply was expressed in early phases of biofilm development and localized to cellular aggregates as early as 4 h postinoculation. S. pneumoniae ply knockout mutants in D39 and TIGR4 backgrounds produced significantly less biofilm biomass than wild-type strains at early time points, both on polystyrene and on human respiratory epithelial cells, cultured under static or continuous-flow conditions. Plys role in biofilm formation appears to be independent of its hemolytic activity, as S. pneumoniae serotype 1 strains, which produce a nonhemolytic variant of Ply, were still able to form biofilms. Transmission electron microscopy of biofilms grown on A549 lung cells using immunogold demonstrated that Ply was located both on the surfaces of pneumococcal cells and in the extracellular biofilm matrix. Altogether, our studies demonstrate a novel role for pneumolysin in the assembly of S. pneumoniae biofilms that is likely important during both carriage and disease and therefore significant for pneumolysin-targeting vaccines under development.
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Glucocorticoid receptor antagonism as a novel therapy for triple-negative breast cancer.
Clin. Cancer Res.
PUBLISHED: 09-09-2013
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Triple-negative breast cancer (TNBC) accounts for 10% to 20% of newly diagnosed invasive breast cancer. Finding effective targets for chemotherapy-resistant TNBC has proven difficult in part because of TNBCs molecular heterogeneity. We have previously reported that likely because of the antiapoptotic activity of glucocorticoid receptor (GR) in estrogen receptor (ER)-negative breast epithelial and cancer cells, high GR expression/activity in early-stage TNBC significantly correlates with chemotherapy resistance and increased recurrence. We hypothesized that pretreatment with mifepristone, a GR antagonist, would potentiate the efficacy of chemotherapy in GR+ TNBCs by inhibiting the antiapoptotic signaling pathways of GR and increasing the cytotoxic efficiency of chemotherapy.
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Mitochondrial binding of ?-enolase stabilizes mitochondrial membrane: Its role in doxorubicin-induced cardiomyocyte apoptosis.
Arch. Biochem. Biophys.
PUBLISHED: 09-01-2013
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?-Enolase is a metabolic enzyme in the catabolic glycolytic pathway. In eukaryotic cells, the subcellular compartmentalization of ?-enolase as well as its multifaceted functions has been identified. Here, we report that ?-enolase is a regulator of cardiac mitochondria; it partially located in the mitochondria of rat cardiomyocytes. Doxorubicin treatment displaced ?-enolase from mitochondria, accompanied by activation of mitochondrial cell death pathway. Furthermore, in isolated mitochondria, recombinant ?-enolase significantly alleviated Ca(2+)-induced loss of membrane potential, swelling of matrix and permeabilization of membrane. In contrast, mitochondria from ?-enolase knockdown H9c2 myoblasts underwent more severe membrane depolarization and swelling after Ca(2+) stimulation. In addition, ?-enolase was further identified to interact with voltage dependent anion channel 1 in the outer membrane of mitochondria, which was weakened by doxorubicin. Collectively, the present study indicates that mitochondria-located ?-enolase has a beneficial role in stabilizing mitochondrial membrane. In cardiomyocytes, the displacement of ?-enolase from mitochondria by doxorubicin may involve in activation of the intrinsic cell death pathway.
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A New Splitting Method for Both Analytical and Preparative LC/MS.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 08-23-2013
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This paper presents a novel splitting method for liquid chromatography/mass spectrometry (LC/MS) application, which allows fast MS detection of LC-separated analytes and subsequent online analyte collection. In this approach, a PEEK capillary tube with a micro-orifice drilled on the tube side wall is used to connect with LC column. A small portion of LC eluent emerging from the orifice can be directly ionized by desorption electrospray ionization (DESI) with negligible time delay (6~10 ms) while the remaining analytes exiting the tube outlet can be collected. The DESI-MS analysis of eluted compounds shows narrow peaks and high sensitivity because of the extremely small dead volume of the orifice used for LC eluent splitting (as low as 4 nL) and the freedom to choose favorable DESI spray solvent. In addition, online derivatization using reactive DESI is possible for supercharging proteins and for enhancing their signals without introducing extra dead volume. Unlike UV detector used in traditional preparative LC experiments, this method is applicable to compounds without chromophores (e.g., saccharides) due to the use of MS detector. Furthermore, this splitting method well suits monolithic column-based ultra-fast LC separation at a high elution flow rate of 4 mL/min. Figure ?
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Association between the cytotoxic T-lymphocyte antigen 4 +49A/G polymorphism and bladder cancer risk.
Tumour Biol.
PUBLISHED: 08-13-2013
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Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is a potent immunoregulatory molecule that suppresses antitumor response by downregulating T cell activation. The most studied CTLA-4 +49A/G polymorphism has been associated with various cancers risks. However, little is known about the association between CTLA-4 +49A/G polymorphism and bladder cancer risk. A hospital-based case-control study was conducted in 300 patients with bladder cancer and 300 healthy controls matched with age and sex. The CTLA-4 +49A/G polymorphism was genotyped using polymerase chain reaction-restriction fragment length polymorphism. Patients with bladder cancer had a significantly lower frequency of CTLA-4 +49GG genotype [odds ratio (OR)?=?0.44, 95 % confidence interval (CI)?=?0.23, 0.85; P?=?0.01] and G allele (OR?=?0.73, 95 % CI?=?0.56, 0.96; P?=?0.02) than healthy controls. When stratifying by the stage, grade, and histological type of bladder cancer, we found no statistical association. This is the first study to highlight the significant association between CTLA-4 +49A/G polymorphism and bladder cancer risk. Additional studies are needed to confirm this finding.
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Factors Associated With Traditional Chinese Medicine Utilization Among Urban Community Health Centers in Hubei Province of China.
Asia Pac J Public Health
PUBLISHED: 07-17-2013
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This study aims to examine resources and utilization of traditional Chinese medicine (TCM) and factors influencing TCM utilization in urban community health centers (CHCs) in Hubei Province of China. A cross-sectional survey including 234 government-owned CHCs was conducted in 2009. One-way analysis of variance analysis and a Poisson regression model were used to examine distribution of TCM resources and factors influencing TCM utilization. This study found unequal distribution of TCM resources among districts. TCM outpatient visits were positively associated with higher economic development districts, lower initial capital investment of the CHCs, health services covered by health insurance, higher qualification of TCM physicians, provision of TCM health records and rehabilitation, and greater availability of herbal medicine. To achieve equal access to TCM services, policy makers should consider the socioeconomic differences and income groups, provide training for TCM physicians, build pathway to recruit senior TCM physicians, and cover more TCM therapies by health insurance.
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Formation of human prostate epithelium using tissue recombination of rodent urogenital sinus mesenchyme and human stem cells.
J Vis Exp
PUBLISHED: 07-16-2013
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Progress in prostate cancer research is severely limited by the availability of human-derived and hormone-naïve model systems, which limit our ability to understand genetic and molecular events underlying prostate disease initiation. Toward developing better model systems for studying human prostate carcinogenesis, we and others have taken advantage of the unique pro-prostatic inductive potential of embryonic rodent prostate stroma, termed urogenital sinus mesenchyme (UGSM). When recombined with certain pluripotent cell populations such as embryonic stem cells, UGSM induces the formation of normal human prostate epithelia in a testosterone-dependent manner. Such a human model system can be used to investigate and experimentally test the ability of candidate prostate cancer susceptibility genes at an accelerated pace compared to typical rodent transgenic studies. Since Human embryonic stem cells (hESCs) can be genetically modified in culture using inducible gene expression or siRNA knock-down vectors prior to tissue recombination, such a model facilitates testing the functional consequences of genes, or combinations of genes, which are thought to promote or prevent carcinogenesis. The technique of isolating pure populations of UGSM cells, however, is challenging and learning often requires someone with previous expertise to personally teach. Moreover, inoculation of cell mixtures under the renal capsule of an immunocompromised host can be technically challenging. Here we outline and illustrate proper isolation of UGSM from rodent embryos and renal capsule implantation of tissue mixtures to form human prostate epithelium. Such an approach, at its current stage, requires in vivo xenografting of embryonic stem cells; future applications could potentially include in vitro gland formation or the use of induced pluripotent stem cell populations (iPSCs).
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Apical F-actin-regulated exocytic targeting of NtPPME1 is essential for construction and rigidity of the pollen tube cell wall.
Plant J.
PUBLISHED: 07-15-2013
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In tip-confined growing pollen tubes, delivery of newly synthesized cell wall materials to the rapidly expanding apical surface requires spatial organization and temporal regulation of the apical F-actin filament and exocytosis. In this study, we demonstrate that apical F-actin is essential for the rigidity and construction of the pollen tube cell wall by regulating exocytosis of Nicotiana tabacum pectin methylesterase (NtPPME1). Wortmannin disrupts the spatial organization of apical F-actin in the pollen tube tip and inhibits polar targeting of NtPPME1, which subsequently alters the rigidity and pectic composition of the pollen tube cell wall, finally causing growth arrest of the pollen tube. In addition to mechanistically linking cell wall construction and apical F-actin, wortmannin can be used as a useful tool for studying endomembrane trafficking and cytoskeletal organization in pollen tubes.
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Transmission of 8 × 480-Gb/s super-Nyquist-filtering 9-QAM-like signal at 100 GHz-grid over 5000-km SMF-28 and twenty-five 100 GHz-grid ROADMs.
Opt Express
PUBLISHED: 07-12-2013
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We experimentally demonstrate a highly filtering-tolerant multi-modulus equalization (MMEQ) process for very aggressively spectrum-shaped 9-ary quadrature-amplitude-modulation (9-QAM)-like polarization division multiplexing quadrature phase shift keying (PDM-QPSK) signal to achieve 400-Gb/s wavelength-division-multiplexing (WDM) channels on the 100-GHz grid for ultra-long-haul reach and high tolerance of the filter narrowing effect caused by reconfigurable optical add-drop multiplexers (ROADMs). We successfully transmitted 8 channels 480-Gb/s super-Nyquist (channel occupancy much less than signal baud rate) WDM signals at 100-GHz grid over 25 × 200 km conventional single-mode fiber-28 (SMF-28) with post Raman amplification and 25 ROADMs at a net spectral efficiency (SE) of 4b/s/Hz, after excluding the 20% soft-decision forward-error-correction (FEC) overhead. The system performance is significantly enhanced by the MMEQ based on 9-QAM-like constellations compared to the conventional 4 point QPSK constellation. A record transmission distance over conventional SMF-28 with a large number of ROADMs is firstly reported on the 400-Gb/s channels at 100-GHz grid.
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Proteinase-activated receptor 2 modulates corticotropin releasing hormone-induced brain-derived neurotrophic factor release from microglial cells.
Cell Biol. Int.
PUBLISHED: 06-22-2013
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Brain-derived neurotrophic factor (BDNF) plays a critical role in the pathogenesis of neuropathic pain, but its regulation of BDNF release is not fully understood. To further understand the regulation of BDNF release, the microglial cell line, C8-D1A (microglia, in short), were cultured as a model. The levels of BDNF were determined by enzyme-linked immunoassay. Apoptotic microglia were assessed by flow cytometry. The protease-activated receptor 2 (PAR2) was activated by tryptase. Exposure to corticotripin releasing hormone (CRH) induced BDNF release from microglia. Apoptosis was evident in microglia after activation by CRH. Tryptase-induced PAR2 activation reduced the frequency of apoptosis of microglia, but enhanced the BDNF levels in the culture medium, which was partially blocked by PAR2 antagonists. We conclude that PAR2 agonists can promote the BDNF release from microglia; the PAR2 antagonists may be a potential therapeutic target to attenuate the BDNF-related neuropathic pain.
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Induction of autophagy contributes to the myocardial protection of valsartan against ischemia?reperfusion injury.
Mol Med Rep
PUBLISHED: 06-21-2013
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The mechanisms underlying the myocardial protection of valsartan against ischemia/reperfusion (I/R) injury are complicated and remain unclear. The aim of this study was to investigate whether autophagy machinery was involved in the protection against I/R injury that is induced by valsartan. In vivo rat hearts were subjected to ischemia by 30 min ligation of the left anterior descending coronary artery, followed by a 120 min reperfusion. 3?methyladenine (3?MA), a specific inhibitor on autophagic sequestration, was used to inhibit autophagy. The hemodynamics, infarct size of the ventricle and LC3B protein were measured. Western blot analysis was performed to investigate the mechanism by which autophagy was induced by valsartan. Valsartan preconditioning resulted in a significant decrease in infarct size and induced autophagy in the rat heart subjected to I/R injury. The hemodynamics assay showed that the valsartan?induced cardiac functional recovery was attenuated by 3?MA. By contrast, 3?MA decreased the improvement induced by valsartan on the histology and infarction of the rat heart subjected to I/R injury. Valsartan preconditioning induced autophagy via the AKT/mTOR/S6K pathway, independent of Beclin1. In conclusion, valsartan preconditioning induced autophagy via the AKT/mTOR/S6K pathway, which contributed to the myocardial protection against I/R injury.
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Imaging intracellular quantum dots: fluorescence microscopy and transmission electron microscopy.
Methods Mol. Biol.
PUBLISHED: 06-11-2013
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Quantum dots (QDs) and other nanoparticles require delivery and targeting for most intracellular applications. Despite many advances, intracellular delivery and targeting remains inefficient with many QDs remaining bound to the plasma membrane rather than internalized into the cell. The fluorescence resulting from these extracellular QDs results in a background signal that competes with intracellular QDs of interest. We present two methods for the reduction and discrimination of signal resulting from plasma membrane-bound QDs. The first method, a photophysical approach, uses an extracellular quencher to greatly reduce the fluorescence signal from extracellular QDs. This method is compatible with fast, widefield, fluorescence imaging in live cells. Results are presented for two extracellular quenchers, QSY-21 and trypan blue, used in combination with 655 nm emitting QDs. The use of an extracellular quencher can be extended to a wide variety of fluorophores. The second method uses transmission electron microscopy (TEM) to image thin (60-70 nm) slices of resin-embedded cells. The use of sectioned cells and high-resolution TEM makes it possible to discriminate between plasma membrane-bound and intracellular QDs. To overcome the difficulties associated with using TEM to image individual QDs in cells, we have utilized a silver enhancement method that significantly improves the contrast of QDs in TEM images.
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Vision insurance, eye care visits, and vision impairment among working-age adults in the United States.
JAMA Ophthalmol
PUBLISHED: 05-28-2013
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To compare rates of eye care visits and vision impairment among working-age adults with vision insurance vs without, among the total sample of Behavioral Risk Factor Surveillance Survey respondents and among a subsample of respondents who had diagnoses of glaucoma, age-related macular degeneration (ARMD), and/or cataract.
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COX-2 is involved in ET-1-induced hypertrophy of neonatal rat cardiomyocytes: Role of NFATc3.
Mol. Cell. Endocrinol.
PUBLISHED: 05-13-2013
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Endothelin-1 (ET-1) is a critical molecule that involved in heart failure. It has been proved that ET-1 stimulation results in cardiac hypertrophy both in vitro and in vivo, but the mechanisms underlying remain largely unknown. In this study, we reported that cyclooxygenase-2 (COX-2) might be an important mediator of hypertrophic responses to ET-1 stimulation. In the cultured rat neonatal cardiomyocytes, ET-1 significantly upregulated the expression and activity of COX-2, which was accompanied by increase in cell surface area and BNP mRNA level. In contrast, ET-1-dependent cardiomyocyte hypertrophy was abolished by COX-2 selective inhibitors, NS-398 and celecoxib, or by COX-2 RNA interference, but the inhibitory effects could be diminished by pretreatment with PGE2. Furthermore, cyclosporin A (CsA) and knockdown of nuclear factor of activated T-cells c3 (NFATc3) inhibited the expression of COX-2 induced by ET-1, and NFATc3 could also bound to the -GGAAA- sequence in the promoter region of rat COX-2 gene, indicating that calcineurin/NFATc3 signaling participated in the transcriptional regulation of COX-2 following ET-1 treatment. These findings provided further insight into the roles of ET-1 in cardiac hypertrophy and suggested a potential therapeutic strategy against cardiac hypertrophy by inhibiting COX-2.
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Identification of the critical amino acid residues of immunoglobulin E and immunoglobulin G epitopes on ?s1-casein by alanine scanning analysis.
J. Dairy Sci.
PUBLISHED: 04-01-2013
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?s1-Casein represents one of the major allergens causing cow milk allergy. Few studies have clearly evaluated immunological relationships between IgE- and IgG-binding epitopes of ?s1-casein. This study aimed to map IgE- and IgG-binding epitopes of ?s1-casein by the serology method, and identify the critical amino acids of ?s1-casein by alanine scanning analysis. Our initial data revealed IgE-binding epitopes located in the sequences of AA 126 to 140, AA 6 to 20, AA 171 to 185, and AA 11 to 25. The sequences at AA 21 to 35, AA 56 to 70, and AA 161 to 175 were recognized by IgG antibodies. The alanine scanning analysis showed that IgE- and IgG-binding epitopes share the same critical AA: arginine at position 22 and phenylalanine at position 23. Results obtained from this study will provide necessary information to alter the cDNA to encode a protein with reduced IgE- or IgG-binding capacity.
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Rasagiline prevents apoptosis induced by PK11195, a ligand of the outer membrane translocator protein (18 kDa), in SH-SY5Y cells through suppression of cytochrome c release from mitochondria.
J Neural Transm
PUBLISHED: 03-25-2013
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Rasagiline protects neuronal cells from cell death caused by various lines of insults. Its neuroprotective function is due to suppression of mitochondrial apoptosis signaling and induction of neuroprotective genes, including Bcl-2 and neurotrophic factors. Rasagiline inhibits the mitochondrial membrane permeabilization, an initial stage in apoptosis, but the mechanism has been elusive. In this paper, it was investigated how rasagiline regulates mitochondrial death cascade in apoptosis induced in SH-SY5Y cells by PK11195, a ligand of the outer membrane translocator protein of 18 kDa. Rasagiline prevented release of cytochrome c (Cyt-c), and the following caspase 3 activation, ATP depletion and apoptosis, but did not inhibit the mitochondrial membrane potential collapse, in contrast to Bcl-2 overexpression. Rasagiline stabilized the mitochondrial contact site and suppressed Cyt-c release into cytoplasm, which should be the critical point for the regulation of apoptosis. Monoamine oxidase was not associated with anti-apoptotic activity of rasagiline in PK11195-induced apoptosis.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.