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Find video protocols related to scientific articles indexed in Pubmed.
Generation of individually modulated femtosecond pulse string by multilayer volume holographic gratings.
Opt Express
PUBLISHED: 11-18-2014
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A scheme to generate individually modulated femtosecond pulse string by multilayer volume holographic grating (MVHG) is proposed. Based on Kogelnik's coupled-wave theory and matrix optics, temporal and spectral expressions of diffracted field are given when a femtosecond pulse is diffracted by a MVHG. It is shown that the number of diffracted sub-pulses in the pulse string equals to the number of grating layers of the MVHG, peak intensity and duration of each diffracted sub-pulse depend on thickness of the corresponding grating layer, whereas pulse interval between adjacent sub-pulses is related to thickness of the corresponding buffer layer. Thus by modulating parameters of the MVHG, individually modulated femtosecond pulse string can be acquired. Based on Bragg selectivity of the volume grating and phase shift provided by the buffer layers, we give an explanation on these phenomena. The result is useful to design MVHG-based devices employed in optical communications, pulse shaping and processing.
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Using the multi-parameter variability of photoplethysmographic signals to evaluate short-term cardiovascular regulation.
J Clin Monit Comput
PUBLISHED: 11-12-2014
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Transient changes in cardiovascular regulatory activities are valuable for clinical monitoring and pathophysiological research. However, there is a lack of effective methods to evaluate short-term cardiovascular regulation. This study explores a photoplethysmography (PPG)-based multi-parameter analytical approach using the period, amplitude and baseline of PPG signals to quantitatively assess cardiovascular regulation over a 30 s period. PPG data were recorded from 31 young healthy subjects during conditions of spontaneous respiration, paced respiration with 15 breaths/min and breath holding, with each condition lasting 30 s. The three indices (SD1, SD2, SD1/SD2) in Poincaré plot of the normalized parameters and the correlations between the parameters or the first differences of the parameters were analyzed. The results showed that compared with spontaneous respiration, SD1 of PPG amplitude increased significantly but the correlations between any two parameters or between the first differences of any two parameters decreased significantly during paced respiration; SD1 and SD1/SD2 of all PPG parameters as well as the correlations of the first differences between any two PPG parameters reduced significantly during breath holding. The results indicate the respiratory induced alterations in cardiovascular autonomic function could be identified by the variability of various PPG parameters or their correlations over 30 s periods. Moreover, the indicators used to quantify the variability of the PPG parameters in this study may provide a feasible and effective way to evaluate short-term cardiovascular regulation.
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Effect of repetitive end-inspiration breath holding on very short-term heart rate variability in healthy humans.
Physiol Meas
PUBLISHED: 11-12-2014
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Very short-term heart rate variability (HRV) is thought to reflect dynamic changes in autonomic nervous activity, which is helpful in understanding the role of autonomic nervous function (ANF) in the mechanisms underlying apnea-induced cardiac arrhythmias. The goal of this study was to investigate the effect of repetitive end-inspiration breath holding on very short-term HRV. A total of 32 young healthy participants took part in the experiments. Three trials were performed, each involving seven repetitive end-inspiration breath holding and a 30?s recovery period between breath holding. Durations of breath holding in the three trials were 1:2:3. The study first evaluated the effect of analyzed data lengths on the stability of HRV indices and determined three HRV indices suitable for very short-term analysis. The results showed that in most cases, during breath holding, the square root of the mean squared differences of successive normal RR intervals (rMSSD) was significantly lower, but normalized units of the power in the low frequency band ranging from 0.04 to 0.15?Hz (nLF) and LF/high frequency (HF) were significantly higher than those during corresponding durations under the normal breathing conditions. On the contrary, during recovery after breath holding, rMSSD was significantly higher but nLF and LF/HF were lower than normal. Moreover, the durations of breath holding had no significant influence on the variations of LF/HF. In addition, as participants repeated the breath holding, HRV indices varied non-linearly. HRV changes may indicate sympathetic activation during breath holding and parasympathetic activation during recovery after breath holding. In conjunction with the existing physiological interpretation based on changes in heart rate, the results may imply that breath holding leads to both cardiac sympathetic and parasympathetic activation simultaneously, which may be a possible pathogenic factor of apnea-induced arrhythmias.
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Application of Frontal Affinity Chromatography to Study the Biomolecular Interactions with Trypsin.
J Chromatogr Sci
PUBLISHED: 11-02-2014
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Trypsin is a serine protease that has been proposed as a potential therapeutic target for metabolic disorders and malignancy diseases, thus the identification of biomolecular interactions of compounds to trypsin could be of great therapeutic importance. In this study, trypsin was immobilized on a monolithic silica capillary column via sol-gel. The binding properties of four small molecules (daidzin, genistin, matrine and oxymatrine) to trypsin were examined using the trypsin affinity columns by frontal analysis. The results indicate that the matrine (dissociation constant, Kd = 7.904 ?M) has stronger interaction with trypsin than the oxymatrine (Kd = 8.204 ?M), whereas daidzin and genistin were nearly have no affinity with trypsin. The results demonstrated that the frontal affinity chromatography can be used for the direct determination of protein-protease inhibitor binding interactions and have several significant advantages, including easy fabricating, reproducible, minimal technological requirements and potential to become a reliable alternative for quantitative studies of biomolecular interactions.
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The role of the strictly conserved positively charged residue differs among the Gram-positive, Gram-negative and chloroplast YidC homologs.
J. Biol. Chem.
PUBLISHED: 11-01-2014
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Recently, the structure of YidC2 from Bacillus halodurans revealed that the conserved positively charged residue within transmembrane (TM) segment one (at position 72) is located in a hydrophilic groove that is embedded in the inner leaflet of the lipid bilayer. The arginine residue was essential for the B. subtilis SpoIIIJ (YidC1) to insert MifM and to complement a SpoIIIJ mutant strain. Here, we investigated the importance of the conserved positively charged residue for the function of the E. coli YidC, S. mutans YidC2, and the chloroplast A. thaliana Alb3. Like for the Gram-positive B. subtilis SpoIIIJ, the conserved arginine was required for functioning of the Gram-positive S. mutans YidC2 and was necessary to complement the E. coli YidC depletion strain and to promote insertion of a YidC-dependent membrane protein synthesized with one but not two hydrophobic segments. In contrast, the conserved positively charged residue was not required for the E. coli YidC or the A. thaliana Alb3 to functionally complement the E. coli YidC depletion strain or to promote insertion of YidC-dependent membrane proteins. Our results also show that the C-terminal half of the helical hairpin structure in cytoplasmic loop C1 is important for the activity of YidC since various deletions in the region either eliminate or impair YidC function. The results here underscore the importance of the cytoplasmic hairpin region for YidC and show that the arginine is critical for the tested Gram-positive YidC homologs but not essential for the tested Gram-negative and chloroplast YidC homologs.
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Endoplasmic Reticulum Stress-Mediated Apoptotic Pathway Is Involved in Corpus Luteum Regression in Rats.
Reprod Sci
PUBLISHED: 10-22-2014
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Endoplasmic reticulum stress (ERS), which is a novel pathway of regulating cellular apoptosis and the function of ERS during corpus luteum (CL) regression, is explored. Early-luteal stage (day 2), mid-luteal stage (day 7), and late-luteal stage (day 14 and 20) were induced, and the apoptosis of luteal cells was detected by a terminal 2'-deoxyuridine 5'-triphosphate nick-end labeling (TUNEL) assay. The apoptotic cells were increased with the regression of CL, especially during the late-luteal stage. The ERS markers glucose-regulated protein 78 (Grp78), CCAAT/enhancer-binding protein homologous protein (CHOP), X-box binding protein 1 (XBP1), activating transcription factor 6? (ATF6?), eukaryotic initiation factor 2? (eIF2?), inositol-requiring protein 1? (IRE1?), caspase 12, and apoptosis marker caspase 3 were analyzed by real-time polymerase chain reaction (PCR) and immunohistochemistry, in agreement with the results of the TUNEL assay; the expression levels of CHOP, caspase 12, and caspase 3 were increased during the process of CL regression. Luteal cells were isolated and cultured in vitro, and the apoptosis of luteal cells was induced by prostaglandin F2?. The ERS was attenuated by the ERS inhibitor tauroursodeoxycholic acid, and the apoptotic rate was analyzed by flow cytometry. The ERS markers Grp78, CHOP, XBP1s, ATF6?, eIF2?, IRE1?, caspase 12, and apoptotic execute marker caspase 3 were analyzed by real-time PCR and immunofluorescence, and the results suggested that the expression of CHOP, caspase 12, and caspase 3 were increased, and there was increased apoptosis of luteal cells. But the expression of IRE1?/XBP1s and eIF2? was not detected. Taken together, the ERS is involved in the CL regression of rats through the CHOP and caspase 12 pathway.
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Macular choroidal thickness in unilateral amblyopic children.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 10-16-2014
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To investigate the choroidal thickness (CT) in children with amblyopia through spectral-domain optical coherence tomography (SD-OCT).
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Association between NOD2 single nucleotide polymorphisms and Grade III-IV acute graft-versus-host disease: A meta-analysis.
Hematology
PUBLISHED: 09-24-2014
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Objectives The effects of NOD2 single nucleotide polymorphisms (SNPs) on Grade III-IV acute graft-versus-host disease (aGVHD) risk are somewhat contradictory in different studies. The aim of the meta-analysis was to clarify the effects of NOD2 SNPs on the incidence of Grade III-IV aGVHD. Methods We searched PubMed, EMBASE, Web of SCIENCE, WanFang and Chinese National Knowledge Infrastructure (CNKI) databases to collect eligible publications. Odds ratios (ORs)with 95% confidence intervals (CIs) were used to assess the association between NOD2 polymorphisms and Grade III-IV aGVHD risk. Results A total of nine studies from eight publications met the inclusion criteria and were included in this meta-analysis. Patient NOD2 SNPs were not associated with aGVHD risk. A tendency of higher risk to develop Grade III-IV aGVHD was found in patients with pairs NOD2 SNPs. Subgroup analyses showed that pairs NOD2 SNPs were associated with Grade III-IV aGVHD in the Caucasian population and in identical sibling donors (IS), but not in matched unrelated donors. In patients who received hematopoietic stem cell transplantation (HSCT) with T-cell depletion and gut decontamination, there was still an association between pairs NOD2 SNPs and Grade III-IV aGVHD risk. Conclusions Our meta-analysis suggests that pairs NOD2 SNPs, not patient NOD2 SNPs, may be associated with Grade III-IV aGVHD risk, especially in the Caucasian population. It is also indicated that in pairs NOD2 polymorphisms group, patients who receive HSCT from IS may experience higher risk of Grade III-IV aGVHD.
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Down regulation of Thrombospondin2 predicts poor prognosis in patients with gastric cancer.
Mol. Cancer
PUBLISHED: 09-22-2014
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Thrombospondins (THBSs) are a family of multidomain and secreted matricellular Ca(2+)-binding glycoproteins which has at least five members encoded by independent genes. As a THBSs family member, Thrombospondin2 (THBS2) has been reported to regulate angiogenesis. Nevertheless, the functions and clinical significance of THBS2 still remains unclear in gastric cancer.
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VAMP8 facilitates cellular proliferation and temozolomide resistance in human glioma cells.
Neuro-oncology
PUBLISHED: 09-12-2014
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Malignant glioma is a common and lethal primary brain tumor in adults. Here we identi?ed a novel oncoprotein, vesicle-associated membrane protein 8 (VAMP8), and investigated its roles in tumorigenisis and chemoresistance in glioma.
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Construction and characterization of novel hirulog variants with antithrombin and antiplatelet activities.
Protein Pept. Lett.
PUBLISHED: 08-30-2014
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The RGD sequence was used to design potent hirudin isoform 3 mimetic peptides with both antithrombin activity and antiplatelet aggregation activity. The RGD and proline were inserted between the catalytic active binding domain (D-Phe-Pro-Arg-Pro) on the N-terminus and the anion-binding exosite binding domain (QGDFEPIPEDAYDE) on the Cterminus. Thrombin titration assay and ATP-induced platelet aggregation test revealed that the peptide with the linker RGDWP or RGDGP possessed potent antithrombin and antiplatelet activities, while other peptides without the Pro residue in the linker only showed antithrombin activity. Similar results were obtained in the RGD-containing hirulog-1 variants. Our study indicates that the inserted Pro residue facilitates the exposure of RGD and the binding of the peptide to glycoprotein IIb/IIIa (GPIIb/IIIa). The strategy of combining the RGD sequence and the Pro residue may be used for future designs of bifunctional antithrombotic agents.
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Correlation of ameloblastin with enamel mineral content.
Connect. Tissue Res.
PUBLISHED: 08-27-2014
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In enamel formation, the deposition of minerals as crystallites starts when the mineralization front first forms at the start of the secretory stage. During maturation, the enamel layer accumulates significant amounts of new mineral as the crystallites grow in volume. Inversely related to mineral gain is loss of protein and water from the forming enamel. Both ameloblastin (Ambn) and enamelin are essential components for formation of a functional enamel layer. The aim of this study was to quantify the proportion of mineral and non-mineral material present in developing enamel relative to Ambn concentration using Ambn mutant mice mated with others overexpressing full-length Ambn from the mouse amelogenin promoter at lower (+), similar (++) or higher (+++) concentration than normal. Mandibular incisors (age: 7 weeks, n?=?8) were imaged by micro-computed tomography and the enamel was analyzed from the apical region to the incisal edge in sequential 1.0?mm volumes of interest. Mineral density was determined using a series of hydroxyapatite (HA) phantoms to calibrate enamel density measurements. At the site where the mandibular incisor emerged into the oral cavity, the enamel volume, mineral weight, and mineral density were reduced when Tg Ambn was expressed at lower or higher levels than normal. While in wild-type the % mineral was >95%, it was negligible in Ambn-/-, 22.3% in Ambn-/-, Tg(+), 75.4% in Ambn-/-, Tg(++), and 45.2% in Ambn-/-, Tg(+++). These results document that the deposition of mineral and removal of non-mineral components are both very sensitive to expressed Ambn concentrations.
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Ameloblast transcriptome changes from secretory to maturation stages.
Connect. Tissue Res.
PUBLISHED: 08-27-2014
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The purpose of this study was to identify the major molecular components in the secretory and maturation stages of amelogenesis through transcriptome analyses. Ameloblasts (40 sections per age group) were laser micro-dissected from Day 5 (secretory stage) and Days 11-12 (maturation stage) first molars. PolyA+ RNA was isolated from the lysed cells, converted to cDNA, and amplified to generate a cDNA library. DNA sequences were obtained using next generation sequencing and analyzed to identify genes whose expression had increased or decreased at least 1.5-fold in maturation stage relative to secretory stage ameloblasts. Among the 9198 genes that surpassed the quality threshold, 373 showed higher expression in secretory stage, while 614 genes increased in maturation stage ameloblasts. The results were cross-checked against a previously published transcriptome generated from tissues overlying secretory and maturation stage mouse incisor enamel and 34 increasing and 26 decreasing expressers common to the two studies were identified. Expression of F2r, which encodes protease activated receptor 1 (PAR1) that showed 10-fold higher expression during the secretory stage in our transcriptome analysis, was characterized in mouse incisors by immunohistochemistry. PAR1 was detected in secretory, but not maturation stage ameloblasts. We conclude that transcriptome analyses are a good starting point for identifying genes/proteins that are critical for proper dental enamel formation and that PAR1 is specifically expressed by secretory stage ameloblasts.
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Transferrin-modified nanostructured lipid carriers as multifunctional nanomedicine for codelivery of DNA and doxorubicin.
Int J Nanomedicine
PUBLISHED: 08-25-2014
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Nanostructured lipid carriers (NLC), composed of solid and liquid lipids, and surfactants are potentially good colloidal drug carriers. The aim of this study was to develop surface-modified NLC as multifunctional nanomedicine for codelivery of enhanced green fluorescence protein plasmid (pEGFP) and doxorubicin (DOX).
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[Result survey analysis of prenatal chromosome karyotyping in an external quality assessment program].
Zhonghua Yi Xue Yi Chuan Xue Za Zhi
PUBLISHED: 08-15-2014
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To analyze the results of prenatal karyotype of the external quality assessment program in 2013 in order to provide references and recommendations for improving the capability and performances of karyotype analysis of prenatal screening laboratories.
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Inflammasome activation and metabolic disease progression.
Cytokine Growth Factor Rev.
PUBLISHED: 08-12-2014
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Innate pattern recognition receptors NLRs are cytosolic sensors that detect endogenous metabolic stress and form a multiprotein complex called the inflammasome, that recruits and activates caspase enzymes mediating the activation of the cytokines IL-1? and IL-18. The innate immune system and metabolic system are evolutionarily conserved, intimately integrated, and functionally dependent. In recent decades, obesity-associated metabolic diseases have been become a worldwide epidemic. Here we review recent evidence that demonstrates the important roles of NLRs and inflammasomes in response to metabolic stress in different tissues.
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Genetic variants in N-myc (and STAT) interactor and susceptibility to glioma in a Chinese Han population.
Tumour Biol.
PUBLISHED: 08-10-2014
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Glioma is one of the most common and lethal brain tumors. N-myc (and STAT) interactor (NMI) gene has been reported in tumorigenesis, and our previous study further showed its implication in glioma progression. To elucidate its involvement in the etiology of glioma, we conducted a case-control study of 875 patients and 1040 controls in a Chinese Han population by genotyping 7 representative single nucleotide polymorphisms (SNPs) in NMI. Allele and genotype frequency distribution of five loci (rs2278089, rs2194492, rs6734376, rs3854012, and rs11730) were significantly different between the cases and controls. Unconditional logistic regression showed that the variant genotypes of rs2278089 [adjusted odds ratio (OR)?=?1.57, P?=?4.23?×?10(-6)], rs2194492 (adjusted OR?=?1.49, P?=?1.20?×?10(-4)), and rs6734376 (adjusted OR?=?0.06, P?=?8.65?×?10(-13)) significantly affected glioma risk compared with the major homozygotes, while the minor homozygotes of rs3854012 (adjusted OR?=?0.54, P?=?4.64?×?10(-6)) and rs11730 (adjusted OR?=?0.60, P?=?1.50?×?10(-4)) showed significant protective effects. Further stratified analyses indicated that these associations remained significant in subgroups of low-grade glioma (LGG) and high-grade glioma (HGG). Additionally, haplotype and diplotype analyses showed consistent results. The Bonferroni correction was applied for all these analyses. Moreover, luciferase reporter gene assays revealed enhanced promoter activity of the C risk allele of rs2194492 in several cell lines compared with the G major allele, suggesting its potential function in transcriptional activation of NMI. Taken together, these results revealed that NMI polymorphisms may contribute to genetic susceptibility to glioma.
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Synergistic effect of amino acids modified on dendrimer surface in gene delivery.
Biomaterials
PUBLISHED: 08-08-2014
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Design of an efficient gene vector based on dendrimer remains a great challenge due to the presence of multiple barriers in gene delivery. Single-functionalization on dendrimer cannot overcome all the barriers. In this study, we synthesized a list of single-, dual- and triple-functionalized dendrimers with arginine, phenylalanine and histidine for gene delivery using a one-pot approach. The three amino acids play different roles in gene delivery: arginine is essential in formation of stable complexes, phenylalanine improves cellular uptake efficacy, and histidine increases pH-buffering capacity and minimizes cytotoxicity of the cationic dendrimer. A combination of these amino acids on dendrimer generates a synergistic effect in gene delivery. The dual- and triple-functionalized dendrimers show minimal cytotoxicity on the transfected NIH 3T3 cells. Using this combination strategy, we can obtain triple-functionalized dendrimers with comparable transfection efficacy to several commercial transfection reagents. Such a combination strategy should be applicable to the design of efficient and biocompatible gene vectors for gene delivery.
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Periodical energy oscillation and pulse splitting in sinusoidal volume holographic grating.
Opt Express
PUBLISHED: 08-05-2014
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This paper presents dynamical diffraction properties of a femtosecond pulse in a sinusoidal volume holographic grating (VHG). By the modified coupled-wave equations of Kogelnik, we show that the diffraction of a femtosecond pulse on the VHG gives rise to periodical energy oscillation and pulse splitting. In the initial stage of diffraction, one diffracted pulse and one transmitted pulse emerge, and energy of the transmitted pulse periodically transfers to the diffracted pulse and vice versa. In the latter stage, both the diffracted and transmitted pulses split into two spatially separated pulses. One pair of transmitted and diffracted pulses propagates in the same direction and forms the output diffracted dual pulses of the VHG, and the other pair of pulses forms the output transmitted dual pulses. The pulse interval between each pair of dual pulses is in linearly proportional to the refractive index modulation and grating thickness. By the interference effect and group velocity difference we give explanations on the periodical energy oscillation and pulse splitting respectively.
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[Signal transducer and activator of transcription-3 inhibitor WP1066 affects human tongue squamous cell carcinoma proliferation and apoptosis in vitro and in vivo].
Zhonghua Kou Qiang Yi Xue Za Zhi
PUBLISHED: 07-18-2014
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To investigate the antitumour molecular mechanisms of WP1066 (STAT-3 inhibitor ) to human tongue squamous cell carcinoma in vitro and in vivo.
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Expression and prognostic significance of TCTN1 in human glioblastoma.
J Transl Med
PUBLISHED: 07-17-2014
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Glioblastoma (GBM) is the most common and lethal intracranial malignancy in adults, with dismal prognosis despite multimodal therapies. Tectonic family member 1 (TCTN1) is a protein involved in a diverse range of developmental processes, yet its functions in GBM remain unclear. This study aims to investigate expression profile, prognostic value and effects of TCTN1 gene in GBM.
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Microcystin-LR exposure to adult zebrafish (Danio rerio) leads to growth inhibition and immune dysfunction in F1 offspring, a parental transmission effect of toxicity.
Aquat. Toxicol.
PUBLISHED: 07-16-2014
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Microcystins (MCs) are algal toxins produced intracellularly within the cyanobacteria cells. MCs exposure exerts great harm to the reproductive system of fish and deteriorates the quality of eggs and sperms, and has further adverse effects on early developmental stages of fish. Whether the MC toxicity can be parentally transmitted to offspring, even though the embryos and larvae are free of MC exposure? In the present study, adult zebrafish were continuously exposed to MC-LR (with dose of 1, 5 and 20 ?g/L) for 30 days. After MC-LR exposure, fertilized eggs were collected and the following F1 generation was reared in water containing no MC-LR until 60 days post fertilization (dpf). In F1 offspring, both body weight and body length were evidently dropped. Some growth and immune related genes were detected using the real-time PCR. The transcriptional levels of these genes significantly decreased in F1 offspring of zebrafish whose parents were treated with 5 and 20 ?g/L MC-LR. The activities of some antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) significantly dropped in 5 and 20 ?g/L MC-LR groups, and the malondialdehyde (MDA) levels markedly increased in all the three treatment groups. Furthermore, distinct pathological changes in liver were observed in F1 zebrafish. Our findings show that the MC-LR exposure to parental zebrafish results in liver damage and evidently influences the growth and immune function in F1 offspring. We consider this damage as a parental transmission effect of microcystin toxicity. Further mechanism studies are necessary to elucidate this transmission effect.
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Knockout of the HCC suppressor gene Lass2 downregulates the expression level of miR-694.
Oncol. Rep.
PUBLISHED: 07-14-2014
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Homo sapiens longevity assurance homolog 2 of yeast LAG (Lass2) catalyzes the synthesis of long-chain ceramide which is an essential element of membranous structures. Deletion of Lass2 is associated with a high risk of spontaneous or DEN-induced hepatocellular carcinoma (HCC), yet the mechanism remains unclear. In the present study, we found extensive vesicles in hepatocytes of one-month-old Lass2-knockout (KO) mice. Hepatic biochemical indices were increased and expression of albumin was attenuated in the one?month Lass2-KO liver. The results indicate that the injuries of the hepatocytes in young Lass2-KO mice, based on the results of Gene Ontology analysis of mRNA microarray of Lass2-KO liver vs. wild-type liver showed 'wounding response' was the mostly possible altered pathway in the Lass2-KO mice. miR-mRNA integrated analysis revealed that miR-694 was downregulated while its target gene tumor necrosis factor ?-induced protein 3 (Tnfaip3) was upregulated, as confirmed by qPCR. The expression of NF-?B which is negatively controlled by Tnfaip3 was detected by qPCR and was found to be downregulated. Herein, we first report that Lass2 deficiency caused the downregulation of miR-694 and the upregulation of its target gene Tnfaip3 in vivo in mice, which may be related to a high risk of occurrence of HCC.
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Long-term real-time monitoring catalytic synthesis of ammonia in a microreactor by VUV-lamp-based charge-transfer ionization time-of-flight mass spectrometry.
Anal. Chem.
PUBLISHED: 07-07-2014
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With respect to massive consumption of ammonia and rigorous industrial synthesis conditions, many studies have been devoted to investigating more environmentally benign catalysts for ammonia synthesis under moderate conditions. However, traditional methods for analysis of synthesized ammonia (e.g., off-line ion chromatography (IC) and chemical titration) suffer from poor sensitivity, low time resolution, and sample manipulations. In this work, charge-transfer ionization (CTI) with O2(+) as the reagent ion based on a vacuum ultraviolet (VUV) lamp in a time-of-flight mass spectrometer (CTI-TOFMS) has been applied for real-time monitoring of the ammonia synthesis in a microreactor. For the necessity of long-term stable monitoring, a self-adjustment algorithm for stabilizing O2(+) ion intensity was developed to automatically compensate the attenuation of the O2(+) ion yield in the ion source as a result of the oxidation of the photoelectric electrode and contamination on the MgF2 window of the VUV lamp. A wide linear calibration curve in the concentration range of 0.2-1000 ppmv with a correlation coefficient (R(2)) of 0.9986 was achieved, and the limit of quantification (LOQ) for NH3 was in ppbv. Microcatalytic synthesis of ammonia with three catalysts prepared by transition-metal/carbon nanotubes was tested, and the rapid changes of NH3 conversion rates with the reaction temperatures were quantitatively measured with a time resolution of 30 s. The high-time-resolution CTI-TOFMS could not only achieve the equilibrium conversion rates of NH3 rapidly but also monitor the activity variations with respect to investigated catalysts during ammonia synthesis reactions.
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Morphological and molecular evidence for two new species of Laetiporus (Basidiomycota, Polyporales) from southwestern China.
Mycologia
PUBLISHED: 07-01-2014
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Two Laetiporus species, L. ailaoshanensis and L. zonatus spp. nov., are described from southwestern China based on morphological and molecular characters. Laetiporus ailaoshanensis is characterized by orange-yellow to reddish orange pileal surface and cream to buff pores when fresh, azonate to faintly zonate pileus, ovoid to ellipsoid basidiospores (5.0-6.2 × 4.0-5.0 ?m), and it has been observed only on Lithocarpus. Laetiporus zonatus is characterized by white to cream pileal surface with buff to clay-buff base when fresh, concentrically zonate basidiocarps, ellipsoid to pyriform or drop-shaped basidiospores (5.8-7.2 × 4.3-5.5 ?m), and it has been found only on Quercus. The phylogenetic relationships of all recognized Laetiporus species were inferred from a combined dataset of ITS and nLSU-rDNA sequences, and L. ailaoshanensis and L. zonatus represent two new lineages in this group.
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Self-storage: a novel family of stimuli-responsive polymer materials for optical and electrochemical switching.
Macromol Rapid Commun
PUBLISHED: 06-24-2014
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For most stimuli-responsive polymer materials (SRPMs), such as polymer gels, micelles, and brushes, the responsive mechanism is based on the solubility or compatibility with liquid media. That basis always results in distorting or collapsing the material's appearance and relies on external liquids. Here, a novel kind of SRPMs is proposed. Unlike most SRPMs, liquid is stored within special domains rather than expelled, so it is deforming-free and relying on no external liquid, which is referred to as self-storage SRPMs (SS-SRPMs). The facile and universal route to fabricate SS-SRPMs allows for another novel family of SRPMs. Furthermore, it is validated that SS-SRPMs can drastically respond to outside temperature like switchers, especially for optical and electrochemical responses. Those features hold prospects for applications in functional devices, such as smart optical lenses or anti-self-discharge electrolytes for energy devices.
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Effect of molecular asymmetry on the charge transport physics of high mobility n-type molecular semiconductors investigated by scanning Kelvin probe microscopy.
ACS Nano
PUBLISHED: 06-23-2014
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We have investigated the influence of the symmetry of the side chain substituents in high-mobility, solution processable n-type molecular semiconductors on the performance of organic field-effect transistors (OFETs). We compare two molecules with the same conjugated core, but either symmetric or asymmetric side chain substituents, and investigate the transport properties and thin film growth mode using scanning Kelvin probe microscopy (SKPM) and atomic force microscopy (AFM). We find that asymmetric side chains can induce a favorable two-dimensional growth mode with a bilayer structure, which enables ultrathin films with a single bilayer to exhibit excellent transport properties, while the symmetric molecules adopt an unfavorable three-dimensional growth mode in which transport in the first monolayer at the interface is severely hindered by high-resistance grain boundaries.
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MicroRNA-377 inhibited proliferation and invasion of human glioblastoma cells by directly targeting specificity protein 1.
Neuro-oncology
PUBLISHED: 06-20-2014
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Increasing evidence has indicated that microRNAs (miRNAs) are strongly implicated in the initiation and progression of glioblastoma multiforme (GBM). Here, we identi?ed a novel tumor suppressive miRNA, miR-377, and investigated its role and therapeutic effect for GBM.
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The efficacy and safety of bevacizumab combined with chemotherapy in treatment of HER2-negative metastatic breast cancer: a meta-analysis based on published phase III trials.
Tumour Biol.
PUBLISHED: 06-16-2014
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Bevacizumab (Bev) combined with chemotherapy significantly improves progression-free survival (PFS) but not overall survival (OS) in patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC). The efficacy and safety depend on the type of chemotherapy combined with Bev. We performed a meta-analysis of phase III trials to evaluate the efficacy and safety of Bev + standard chemotherapy for HER2-negative MBC. The Cochrane Central Register of Controlled Trials, the Cochrane databases, EMBASE, MEDLINE, and ClinicalTrials.gov were analyzed. The primary outcomes included PFS, OS, and toxicity. Event-based hazard ratios (HRs) and relative risks (RRs) were expressed with the 95 % confidence intervals (CIs). Four randomized controlled trials consisting of 3082 patients were included. Bev + standard chemotherapy improved PFS (HR 0.70, CI 0.64-0.77, P?=?0.000) but had no effect on OS (HR 0.92, CI 0.82-1.02, P?=?0.119). Bev + chemotherapy increased the incidence of febrile neutropenia (RR 1.45, CI 1.00 to 2.09, P?=?0.048), proteinuria (RR 11.68, CI 3.72-36.70, P?=?0.000), sensory neuropathy (RR 1.33, CI 1.05-1.70, P?=?0.020), and grade ?3 hypertension (RR 13.94, CI 7.06-27.55, P?=?0.000). No differences in efficacy were observed between Bev + paclitaxel and Bev + capecitabine (Cape), but Bev + Cape increased the incidence of neutropenia. Bev + standard chemotherapy improved PFS in HER2-negative MBC patients. No benefit in OS was observed. Bev + Cape and Bev + paclitaxel had similar treatment efficacy, but Bev + Cape had a higher incidence of neutropenia.
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[Molecular mechanisms of SNARE proteins in regulating autophagy].
Yi Chuan
PUBLISHED: 06-16-2014
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Autophagy is a self-protective mechanism that degrades inner and outer invaded substances to sustain self-maintenance. SNARE (Soluble N-ethylmaleimide-sensitive factor attachment protein receptors) hypothesis suggests important roles of SNARE proteins in the cellular activities of substance transport and specific membrane fusion, unveiling the molecular mechanisms of normal and physiological activities within a cell. Since autophagy involves membrane fusions from the birth of autophagosomes to the formation of autolysosomes, we review recent research progress on the roles of SNARE proteins in regulating autophagy.
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Time-Course Changes of Steroidogenic Gene Expression and Steroidogenesis of Rat Leydig Cells after Acute Immobilization Stress.
Int J Mol Sci
PUBLISHED: 06-12-2014
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Leydig cells secrete testosterone, which is essential for male fertility and reproductive health. Stress increases the secretion of glucocorticoid (corticosterone, CORT; in rats), which decreases circulating testosterone levels in part through a direct action by binding to the glucocorticoid receptors (NR3C1) in Leydig cells. The intratesticular CORT level is dependent on oxidative inactivation of glucocorticoid by 11?-hydroxysteroid dehydrogenase 1 (HSD11B1) in Leydig cells. In the present study, we investigated the time-course changes of steroidogenic gene expression levels after acute immobilization stress in rats. The plasma CORT levels were significantly increased 0.5, 1, 3 and 6 h after immobilization stress, while plasma testosterone levels were significantly reduced 3 and 6 h, after stress and luteinizing hormone (LH) did not change. Immobilization stress caused the down-regulation of Scarb1, Star and Cyp17a1 expression levels in the rat testis starting at the first hour of stress, ahead of the significant decreases of plasma testosterone levels. Other mRNA levels, including Cyp11a1, Hsd3b1 and Hsd17b3, began to decline after 3 h. Hsd11b1 and Nos2 mRNA levels did not change during the course of stress. Administration of glucocorticoid antagonist RU486 significantly restored plasma testosterone levels. In conclusion, Scarb1, Star and Cyp17a1 expression levels are more sensitive to acute stress, and acute immobilization stress causes the decline of the steroidogenic pathway via elevating the levels of glucocorticoid, which binds to NR3C1 in Leydig cells to inhibit steroidogenic gene expression.
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Identification and characterization of novel inhibitors of Mammalian aspartyl aminopeptidase.
Mol. Pharmacol.
PUBLISHED: 06-09-2014
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Aspartyl aminopeptidase (DNPEP) has been implicated in the control of angiotensin signaling and endosome trafficking, but its precise biologic roles remain incompletely defined. We performed a high-throughput screen of ?25,000 small molecules to identify inhibitors of DNPEP for use as tools to study its biologic functions. Twenty-three confirmed hits inhibited DNPEP-catalyzed hydrolysis of angiotensin II with micromolar potency. A counter screen against glutamyl aminopeptidase (ENPEP), an enzyme with substrate specificity similar to that of DNPEP, identified eight DNPEP-selective inhibitors. Structure-activity relationships and modeling studies revealed structural features common to the identified inhibitors, including a metal-chelating group and a charged or polar moiety that could interact with portions of the enzyme active site. The compounds identified in this study should be valuable tools for elucidating DNPEP physiology.
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GO-COO-HP-?-CD nanosphere: a complex construction and its drug-loading properties.
Nanotechnology
PUBLISHED: 06-04-2014
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A novel nanosphere based on carboxylated GO (GO-COOH) and hydroxypropyl-beta-CD (HP-?-CD) was synthesized to construct a complex of GO-COO-HP-?-CD. The complex formation process was studied using spectral characterization and transmission electron microscopy (TEM). X-ray diffraction and energy dispersive spectroscopy patterns show that HP-?-CD molecules either cover or intercalate into GO-COOH interlayers in the complex. Fourier transform infrared spectroscopy results indicate that GO-COOH and HP-?-CD are linked with covalent bonds formed via esterification. When employed as nanohybrid drug carriers for dexamethasone, the inclusion displays good dispersibility validated by dynamic light scattering (DLS). Cytotoxicity assays and hemolysis testing demonstrate that the nanospheres possess good biological compatibility. The loading capacity of dexamethasone is as high as 32.33%, with loading efficiency 64.66%.
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[Effect of Er:YAG laser on the dynamic changes in subgingival flora in type 2 diabetic patients with periodontitis].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 06-03-2014
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To observe the changes in subgingival microflora before and after Er:YAG laser treatment on diabetic patients with periodontitis, and to compare with the subgingival microflora of chronic periodontitis.
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Time-averaged albumin predicts the long-term prognosis of IgA nephropathy patients who achieved remission.
J Transl Med
PUBLISHED: 05-22-2014
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Primary IgA nephropathy (IgAN) is the most common form of idiopathic glomerulonephritis worldwide. Although most patients are able to achieve remission with the current therapy, a large number of patients will still progress to end-stage renal disease. This study aimed to evaluate kidney disease progression and the risk factors for progression in IgAN patients who achieved remission.
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High-fat diet induces early-onset diabetes in heterozygous Pax6 mutant mice.
Diabetes Metab. Res. Rev.
PUBLISHED: 05-13-2014
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Type 2 diabetes is caused by interactions between genetic and environmental factors. Our previous studies reported that paired box?6 mutation heterozygosity (Pax6(m/+)) led to defective proinsulin processing and subsequent abnormal glucose metabolism in mice at 6 ?months of age. However, high-fat diet exposure could be an important incentive for diabetes development. In this study, we aimed to develop a novel diabetic model imitating human type 2 diabetes by exposing Pax6(m/+) mice to high-fat diet and to explore the underlying mechanism of diabetes in this model.
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Can magnetic resonance spectroscopy differentiate endometrial cancer?
Eur Radiol
PUBLISHED: 05-13-2014
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To investigate whether the choline-containing compounds (Cho) obtained from three-dimensional (1)H magnetic resonance (MR) spectroscopy can differentiate endometrial cancer (ECa) from benign lesions in endometria or in submucosa (BLs-ESm) and is associated with the aggressiveness of ECa.
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Urinary excretion of liver-type FABP as a new clinical marker for the progression of obstructive nephropathy.
Biomark Med
PUBLISHED: 05-07-2014
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The aim of this article was to investigate the performance and predictive value of urinary liver-type FABP (uL-FABP) and urinary NGAL (uNGAL) for renal function and prognosis in obstructive nephropathy (ON).
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Metformin inhibits nuclear factor-?B activation and inflammatory cytokines expression induced by high glucose via adenosine monophosphate-activated protein kinase activation in rat glomerular mesangial cells in vitro.
Chin. Med. J.
PUBLISHED: 05-06-2014
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The renoprotective mechanisms of adenosine monophosphate (AMP)-activated protein kinase (AMPK) agonist - metformin have not been stated clearly. We hypothesized that metformin may ameliorate inflammation via AMPK interaction with critical inflammatory cytokines. The aim of this study was to observe the effects of metformin on expression of nuclear factor-?B (NF-?B), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1) and transforming growth factor-beta 1 (TGF-?1) induced by high glucose (HG) in cultured rat glomerular mesangial cells (MCs).
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High p-Smad2 expression in stromal fibroblasts predicts poor survival in patients with clinical stage I to IIIA non-small cell lung cancer.
World J Surg Oncol
PUBLISHED: 04-28-2014
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Increasing evidence indicates that the TGF?/Smad signaling pathway plays a prominent role in tumor initiation, progression, and metastasis. Therefore, we investigate the expression of p-Smad2 in surgical resection specimens from non-small cell lung cancer, and evaluate the prognostic significance of p-Smad2 expression in stromal fibroblasts and cancer cells for patients with clinical stage I to IIIA non-small cell lung cancer.
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Vitamin C mitigates oxidative stress and tumor necrosis factor-alpha in severe community-acquired pneumonia and LPS-induced macrophages.
Mediators Inflamm.
PUBLISHED: 04-24-2014
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Oxidative stress is an important part of host innate immune response to foreign pathogens. However, the impact of vitamin C on oxidative stress and inflammation remains unclear in community-acquired pneumonia (CAP). We aimed to determine the effect of vitamin C on oxidative stress and inflammation. CAP patients were enrolled. Reactive oxygen species (ROS), DNA damage, superoxide dismutases (SOD) activity, tumor necrosis factor-alpha (TNF-?), and IL-6 were analyzed in CAP patients and LPS-stimulated macrophages cells. MH-S cells were transfected with RFP-LC3 plasmids. Autophagy was measured in LPS-stimulated macrophages cells. Severe CAP patients showed significantly increased ROS, DNA damage, TNF-?, and IL-6. SOD was significantly decreased in severe CAP. Vitamin C significantly decreased ROS, DNA damage, TNF-?, and IL-6. Vitamin C inhibited LPS-induced ROS, DNA damage, TNF-?, IL-6, and p38 in macrophages cells. Vitamin C inhibited autophagy in LPS-induced macrophages cells. These findings indicated that severe CAP exhibited significantly increased oxidative stress, DNA damage, and proinflammatory mediator. Vitamin C mitigated oxidative stress and proinflammatory mediator suggesting a possible mechanism for vitamin C in severe CAP.
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Mg2+ binding affects the structure and activity of ovomucin.
Int. J. Biol. Macromol.
PUBLISHED: 04-18-2014
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Metal-protein interaction for regulating the function and structure of proteins is of major interest. We demonstrate here that the addition of 9 ?mol Mg2+ per mg ovomucin resulted in a 2.0-fold increase in the adhesion capacity of ovomucin to New Disease Virus (NDV) using ELISA method. The hemagglutinin inhibition rate of 100 ?g/mL ovomucin-Mg2+ mixture (9 ?mol Mg2+ per mg ovomucin) to NDV increased to 55.61%, which is significantly higher than that of the pure ovomucin (P<0.01). Binding characteristics of ovomucin to Mg2+ were then evident by fluorescence and FT-IR spectroscopy as well as dynamic light scattering (DLS) technology. Fluorescence and FT-IR spectroscopy results suggest that Mg2+ prefers to interact with the carbohydrate moiety of ovomucin without significant changes in the secondary structure when Mg2+ concentration is less than 9 ?mol/mg ovomucin. When Mg2+ increases to 16 ?mol/mg ovomucin, it gives rise to changes in secondary structure, and forms a more compact configuration. This is supported by the hydrodynamic radius of ovomucin with and without Mg2+ binding as examined by DLS. The Mg2+ bound in regulating the structure and activity of ovomucin provided important insight into the effect of metal ions on ovomucin binding to pathogens.
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Distribution of enterovirus 71 RNA in inflammatory cells infiltrating different tissues in fatal cases of hand, foot, and mouth disease.
Arch. Virol.
PUBLISHED: 04-16-2014
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In previous studies of hand, foot, and mouth disease patients fatally infected with enterovirus 71 (EV71), the distribution of viral protein, but not the genome, was determined. To understand the pathogenesis of EV71, however, it is important to investigate the spread of the viral genome. There have been no pathological studies of in situ EV71 viral RNA in inflammatory cells infiltrating various tissues of fatal cases. We therefore first investigated the distribution and classification of inflammatory cells in various tissues and then performed in situ EV71 RNA hybridization in these tissues to better understand the pathogenesis of EV71 infection. EV71 RNA was found mainly in inflammatory cells infiltrating the central nervous system (CNS), intestines, lungs, and tonsils. Most EV71 RNA-positive inflammatory cells in the CNS were macrophages/microglia and neutrophils infiltrating the perivascular cuffing, microglial nodule, neuronophagia, and meninges. CD68+ macrophages and CD15+ neutrophils were diffusely distributed in tissues with severe pathological changes. This study demonstrates the presence of EV71 RNA in inflammatory cells infiltrating tissues in fatally infected patients. Our findings suggest that fatal EV71 infection with extensive infiltration of macrophages/microglia and neutrophils into the CNS results in severe neurological lesions.
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Structural insights into the T6SS effector protein Tse3 and the Tse3-Tsi3 complex from Pseudomonas aeruginosa reveal a calcium-dependent membrane-binding mechanism.
Mol. Microbiol.
PUBLISHED: 04-10-2014
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The opportunistic pathogen Pseudomonas aeruginosa uses the type VI secretion system (T6SS) to deliver the muramidase Tse3 into the periplasm of rival bacteria to degrade their peptidoglycan (PG). Concomitantly, P. aeruginosa uses the periplasm-localized immunity protein Tsi3 to prevent potential self-intoxication caused by Tse3, and thus gains an edge over rival bacteria in fierce niche competition. Here, we report the crystal structures of Tse3 and the Tse3-Tsi3 complex. Tse3 contains an annexin repeat-like fold at the N-terminus and a G-type lysozyme fold at the C-terminus. One loop in the N-terminal domain (Loop 12) and one helix (?9) from the C-terminal domain together anchor Tse3 and the Tse3-Tsi3 complex to membrane in a calcium-dependent manner in vitro, and this membrane-binding ability is essential for Tse3's activity. In the C-terminal domain, a Y-shaped groove present on the surface likely serves as the PG binding site. Two calcium-binding motifs are also observed in the groove and these are necessary for Tse3 activity. In the Tse3-Tsi3 structure, three loops of Tsi3 insert into the substrate-binding groove of Tse3, and three calcium ions present at the interface of the complex are indispensable for the formation of the Tse3-Tsi3 complex.
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Development and evaluation of a patching treatment questionnaire for Chinese amblyopic children.
Chin. Med. J.
PUBLISHED: 04-09-2014
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Amblyopia is a common disease for children. The main treatment approach for amblyopia is to patch the normally sighted eye and force the use of the amblyopic eye. However, patching treatment in children may negatively impact psychological well-being of both the child and family. At present, no specific questionnaire is available to assess the health-related quality of life (HRQoL) of amblyopic treatment for children and their families in China. The purpose of our study was to develop a Chinese version of patching treatment questionnaire, and evaluate its reliability and validity.
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Co-delivery of plasmid DNA and doxorubicin by solid lipid nanoparticles for lung cancer therapy.
Int. J. Mol. Med.
PUBLISHED: 04-08-2014
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The co-delivery of DNA and antitumor drugs has the potential to treat cancer. In this study, we aimed to develop surface-modified, co-encapsulated solid lipid nanoparticles (SLN) containing enhanced green fluorescence protein plasmid (pEGFP) and doxorubicin (DOX) in order to create a multifunctional delivery system that targets lung cancer cells, in an effort to improve the efficacy of cancer therapy. DOX- and pEGFP-loaded SLN were prepared separately and then mixed to form co-encapsulated SLN (SLN/DE). Transferrin (Tf)-containing ligands were used for the surface coating of the vectors. The in vitro transfection efficiency of the modified vectors was evaluated using a human alveolar adenocarcinoma cell line (A549 cells) and the in vivo transfection efficiency of the modified vectors was evaluated using mice bearing A549 tumors. The Tf-modified DOX and pEGFP co-encapsulated SLN (T-SLN/DE) had a particle size of 267 nm with a 42 mV surface charge. The in vitro cytotoxicity of T-SLN/DE was low (cell viability was between 80 and 100% compared with the controls). T-SLN/DE displayed a remarkable therapeutic effect both in drug delivery and gene therapy. In conclusion, our results demonstrate that the multifunctional delivery system can improve the efficacy of cancer therapy through the combination of gene therapy and chemotherapy. In addition, the coating of active targeting ligands can improve the efficacy of the carriers at targeting lung cancer cells. Thus, the novel gene and drug delivery system offers an effective strategy for lung cancer gene therapy.
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Contributions of nonleaf organs to the yield of cotton grown with different water supply.
ScientificWorldJournal
PUBLISHED: 04-01-2014
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The objectives of this experiment were (i) to determine the effect of water supply on the photosynthetic capacity of leaves, bracts, capsule walls, and stalks of cotton at different growth stages and (ii) to determine the contributions of these nonleaf organs to whole plant photosynthesis. Water deficit reduced the total surface area per plant but increased the proportion of nonleaf to total plant surface area. Net photosynthetic rates of leaves declined rapidly beginning 25 days after anthesis. In contrast, the net photosynthetic rates of bracts and capsule walls were insensitive to soil moisture stress and decreased by a small amount between 25 and 45 days after anthesis. The relative contribution of bracts and stalks to canopy apparent photosynthesis (CAP) increased under water deficit conditions. Cotton seed weight in the conventional irrigation treatment decreased by 10.1-29.7% when the bolls (capsule walls plus bracts) were darkened and by 5.3-9.9% when the stalks were darkened. On a percentage basis, both boll photosynthesis and stalk photosynthesis contributed more to seed weight when the plants were grown under water deficit conditions rather than nondeficit conditions. In conclusion, nonleaf organs contribute significantly to yield when cotton plants are under water stress during late growth stages.
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Cryofibrinogenemia After a Liver Transplant: First Reported Case Posttransplant and a Case-Based Review of the Nontransplant Literature.
Exp Clin Transplant
PUBLISHED: 04-01-2014
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Cryofibrinogenemia is a rare disorder in which plasma, not serum, forms a cryoprecipitate. Patients with cryofibrinogenemia may be asymptomatic, or they may have painful ulcers, purpura, livedo reticularis, Raynaud phenomenon, perniosis of the extremities, thrombosis, and arthralgia. Cryofibrinogenemia may be primary or secondary to an underlying disorder such as connective tissue disease, malignancy, infection, drugs, or thromboembolic disease. Here, we present a 41-year-old woman with a pancreatic neuroendocrine tumor who underwent a Whipple procedure in 2003 followed by 2 liver transplants for hepatic metastases. Three years posttransplant, we discovered a biopsy-proven metastatic lesion in her femur. Five years posttransplant, she developed acute, severe pain in both feet, and was found to have cryofibrinogenemia despite immunosuppression posttransplant. Testing for connective tissue diseases and hematologic malignancy were negative. She was treated with high-dose prednisone, which completely resolved her symptoms. We also conducted a review of the literature via a PubMed search to summarize the association of cryofibrinogenemia with malignancy and treating cryofibrinogenemia with corticosteroids. Our study is the first reported case of cryofibrinogenemia that developed secondary to a neuroendocrine tumor posttransplant. Our report suggests that cryofibrinogenemia may occur despite immunosuppression adequate to prevent graft rejection, and that high-dose corticosteroids are an effective treatment for posttransplant cryofibrinogenemia.
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[Comparative studies on cariogenic bacteria of the root surface before and after post-core crown restoration in aged people].
Hua Xi Kou Qiang Yi Xue Za Zhi
PUBLISHED: 03-27-2014
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To investigate the changes in the quantity of colonizing Streptococcus mutans(S. mutans) and Actinomyces on the root surface plaque before and after post-core crown restoration of the mandibular first molars in the elderly patients.
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The S1P1 receptor-selective agonist CYM-5442 reduces the severity of acute GVHD by inhibiting macrophage recruitment.
Cell. Mol. Immunol.
PUBLISHED: 03-21-2014
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FTY720, an agonist for four of the five known sphingosine-1-phosphate (S1P) receptors, has been reported to inhibit acute graft-versus-host disease (aGVHD). Because FTY720 functions through multiple S1P receptors, the mechanism of action through one or more of these receptors may account for its side effects. Thus, more selective S1P receptor modulators are needed to evaluate the roles of different S1P receptors and their therapeutic efficacies. In this study, we investigated the effect of an S1P1-selective agonist, CYM-5442, on the progression of aGVHD. We showed that CYM-5442 significantly inhibited but did not prevent aGVHD. CYM-5442 did not affect the infiltration of the donor T cells into the target organs, while the number of macrophages in GVHD organs was significantly reduced by CYM-5442 treatment. In vivo proliferation assays showed that the proliferation of macrophages was not suppressed by CYM-5442. Further studies using human endothelial cells demonstrated that CYM-5442 treatment downregulated CCL2 and CCL7 expression in endothelial cells, therefore reducing the migration of monocytes, from which tissue macrophages originate. Our data demonstrate the therapeutic efficacy of an S1P1-selective agonist in aGVHD and its possible mechanism of action. The results suggest that further investigations are needed regarding CYM-5442 as a potential therapeutic regimen for aGVHD.Cellular & Molecular Immunology advance online publication, 4 August 2014; doi:10.1038/cmi.2014.59.
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Small molecule-folic acid modification on nanopatterned PDMS and investigation on its surface property.
Biomed Microdevices
PUBLISHED: 03-15-2014
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Folic acid (or folate, FA) has attracted considerable attention for cancer therapy. As one small molecule, its receptor (folate receptor, FR) is significantly overexpressed on the surface of many human tumor cells compared with normal cells. In this work, physical and chemical coupled modification method, that is the combination of nanoimprinting technique and graft polymerization, was adopted to modify FA on nanopatterned polydimethylsiloxane (PDMS) surface for possible application in micro-nanofluidic cytology. The surface property of differently treated PDMS was characterized by FTIR, AFM and contact angle measurement. AO/PI double staining, cell counting and MTT method were performed to examine the potential influence of FA modified nanopatterned PDMS on human cervical carcinoma (HeLa) cell behavior. Both FA modification and nanostructure have positive effect on the growth and viability of HeLa cells. It is the first time that the small molecule-folic acid was used to immobilize on the surface of PDMS in order to improve its surface property.
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Transforming growth factor-?1 and ?-smooth muscle actin in stromal fibroblasts are associated with a poor prognosis in patients with clinical stage I-IIIA nonsmall cell lung cancer after curative resection.
Tumour Biol.
PUBLISHED: 03-10-2014
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The aims of this study were to investigate the expression of transforming growth factor-?1 (TGF-?1) and ?-smooth muscle actin (?-SMA) in surgical resection specimens from nonsmall cell lung cancer (NSCLC) and to evaluate the prognostic significance of this gene expression in stromal fibroblasts for patients with clinical stage I-IIIA NSCLC. The immunohistochemical expression of TGF-?1 and ?-SMA was evaluated in 78 formalin-fixed paraffin-embedded tumor specimens from clinical stage I-IIIA NSCLC. Correlations between this gene expression and the clinicopathologic characteristics were determined by chi-square test. The prognostic impact of this gene expression in stromal fibroblasts with regard to overall survival (OS) was determined by Kaplan-Meier and Cox hazard proportional model. The percentages of high TGF-?1 expression in stromal fibroblasts and cancer cells were 19.2 % (15/78) and 35.9 % (28/78), respectively. There were 28.2 % (22/78) of patients with high ?-SMA expression in stromal fibroblasts. The analysis revealed a significant positive association between TGF-?1 expression in stromal fibroblasts and in cancer cells (? (2)?= 4.86, p = 0.03). No significant association was found between TGF-?1 in cancer cells and ?-SMA expression in stromal fibroblasts (? (2)?= 0.978, p = 0.326). The 3-year OS rates with low and high TGF-?1 expression in stromal fibroblasts were 52.4 and 26.7 %, respectively (? (2)?= 5.42, p = 0.019). The 3-year OS rates with low and high ?-SMA expression in stromal fibroblasts were 53.9 and 31.0 %, respectively (? (2)?=5.01, p=0.025). The multivariate analysis revealed that clinical stage and TGF-?1 and ?-SMA expression levels in stromal fibroblasts were identified as independent predictive factors of OS. The results suggest that the expression level of TGF-?1 and ?-SMA in stromal fibroblasts may have prognostic significance in patients with clinical stage I-IIIA NSCLC after curative resection.
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Synchrotron radiation imaging is a powerful tool to image brain microvasculature.
Med Phys
PUBLISHED: 03-06-2014
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Synchrotron radiation (SR) imaging is a powerful experimental tool for micrometer-scale imaging of microcirculation in vivo. This review discusses recent methodological advances and findings from morphological investigations of cerebral vascular networks during several neurovascular pathologies. In particular, it describes recent developments in SR microangiography for real-time assessment of the brain microvasculature under various pathological conditions in small animal models. It also covers studies that employed SR-based phase-contrast imaging to acquire 3D brain images and provide detailed maps of brain vasculature. In addition, a brief introduction of SR technology and current limitations of SR sources are described in this review. In the near future, SR imaging could transform into a common and informative imaging modality to resolve subtle details of cerebrovascular function.
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A polysaccharide from Grifola frondosa relieves insulin resistance of HepG2 cell by Akt-GSK-3 pathway.
Glycoconj. J.
PUBLISHED: 02-28-2014
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Grifola frondosa is an important fungal research resource. However, there was little report about hyperglycemic activity of Grifola frondosa polysaccharide on insulin resistance in vitro. In this study, the hypoglycemic activity of a polysaccharide obtained from Grifola frondosa (GFP) on HepG2 cell and hpyerglycemic mechanism were investigated. The purity of the isolated polysaccharides was examined by HPLC. In this research, it was found that GFP enhanced the absorption of glucose of HepG2 cells in a dose dependent manner at 24 h of 30 ugmL(-1). GC-MS and FT-IR spectroscopy analysis results showed that glucose and galactose were the dominant monosaccharides in GFP and the major component of GFP was ?-pyranoside. Western-blotting results showed that the HepG2 cell model treated with GFP activated the insulin receptor protein (IRS) in the cell membrane and increased phosphorylated-AktSer473 expression, which had an inhibition of glycogen synthase kinase (GSK-3). The down-regulation of GSK-3 stimulated synthesis of intracellular glycogen. The results above suggested that the GFP increased the metabolism of glucose and stimulated synthesis of intracellular glycogen through the Akt/GSK-3 pathway.
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Physicochemical properties of peanut protein isolate-glucomannan conjugates prepared by ultrasonic treatment.
Ultrason Sonochem
PUBLISHED: 02-17-2014
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Peanut protein isolate (PPI) was glycated with glucomannan through classical heating or ultrasound treatment in this work. The physicochemical properties of PPI-glucomannan conjugates prepared by ultrasound treatment were compared to those prepared by classical heating. Compared with classical heating, ultrasound treatment could accelerate the graft reaction between PPI and glucomannan and improve the concentration of available free amino groups of PPI. Solubility and emulsifying properties of the conjugates obtained by ultrasound treatment were both improved as compared to those obtained by classical heating and native PPI. Decreases of lysine and arginine contents during the graft reaction indicated that these two amino acid residues attended the covalent linkage between PPI and glucomannan. Structural feature analyses suggested that conjugates obtained by ultrasound treatment had less ?-helix, more ?-structures and random coil, higher surface hydrophobicity and less compact tertiary structure as compared to those obtained by classical heating and native PPI.
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Analysis of compositional monosaccharides in fungus polysaccharides by capillary zone electrophoresis.
Carbohydr Polym
PUBLISHED: 02-11-2014
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A rapid analytical method of capillary zone electrophoresis (CZE) was established for the simultaneous separation and determination of 10 monosaccharides (aldoses and uronic acids). The monosaccharides were labeled with 1-phenyl-3-methyl-5-pyrazolone (PMP), and subsequently separated using an uncoated capillary (50 ?m i.d. × 58.5 cm) and detected by UV at 245 nm with pH 11.0, 175 mM borate buffer at voltage 20 kV and capillary temperature 25 °C by CZE. The 10 PMP-labeled monosaccharides were rapidly baseline separated within 20 min. The optimized CZE method was successfully applied to the simultaneous separation and identification of the monosaccharide composition in Termitomyces albuminosus polysaccharides (TAPs) and Panus giganteus polysaccharides (PGPs). The quantitative recovery of the component monosaccharides in the fungus polysaccharides was in the range of 92.0-101.0% and the CV value was lower than 3.5%. The results demonstrate that the proposed CZE method is precise and practical for the monosaccharide analysis of fungus polysaccharides.
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Unidirectional thermal diffusion in bimetallic Cu@Au nanoparticles.
ACS Nano
PUBLISHED: 01-30-2014
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Understanding the atomic diffusions at the nanoscale is important for controlling the synthesis and utilization of nanomaterials. Here, using in situ X-ray absorption spectroscopy coupled with theoretical calculations, we demonstrate a so far unexplored unidirectional diffusion from the Au shell to the Cu core in thermally alloying Cu@Au core@shell architecture of ca. 7.1 nm. The initial diffusion step at 423 K is found to be characterized by the formation of a diffusion layer composed of a Au-dilute substitutional CuAu-like intermetallic compound with short Cu-Au bond length (2.61 Å). The diffusion further happens by the migration of the Au atoms with large disorder into the interior Cu matrix at higher temperatures (453 and 553 K). These results suggest that the structural preference of a CuAu-like compound, along with the nanosized effect, plays a critical role in determining the atomic diffusion dynamics.
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Association between cyclooxygenase-2 gene polymorphisms and head and neck squamous cell carcinoma risk.
J Craniofac Surg
PUBLISHED: 01-29-2014
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Cyclooxygenase-2 (COX-2) is an inducible enzyme that catalyzes prostaglandins through inflammatory response, which may be involved in autoimmune diseases and cancer pathogenesis. Two potentially functional genetic single-nucleotide polymorphisms (COX-2 -1195G>A and 8473T>C) were supposed to contribute to head and neck squamous cell carcinoma (HNSCC) susceptibility. The aim of this study was to determine the association of these polymorphisms with HNSCC susceptibility in a Chinese Han population. In this study, 2 SNPs were genotyped by TaqMan methods in a patient-control study including 260 patients with HNSCC and 1047 cancer-free controls in a Chinese Han population. We found significant difference in the frequency of alcohol consumption between the patients with HNSCC and controls (P < 0.001), but the genotype frequencies of the 2 polymorphisms were not significantly different between the patients and controls. Further stratified analysis indicated that none of the genotypes were associated with increased risk for HNSCC. This research indicated that the COX-2 -1195G>A and 8473T>C polymorphisms may not be involved in the development of HNSCC in the Chinese Han population. However, further perspective studies are warranted to test these findings and further investigate the potential interactions involving the COX-2 polymorphism and HNSCC.
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Retinoic acid receptor ? (Rarg) and nuclear receptor subfamily 5, group A, member 2 (Nr5a2) promote conversion of fibroblasts to functional neurons.
J. Biol. Chem.
PUBLISHED: 01-23-2014
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Somatic cells can be reprogrammed to neurons and various other cell types with retrovirus or lentivirus. The limitation of this technology is that these genome-integration viruses may increase the risk of gene mutation and cause insertional mutagenesis. We recently found that non-integration adenovirus carrying neuronal transcription factors can induce fibroblasts to neurons. However, the conversion efficiency by the adenovirus is lower than that of the retrovirus or lentivirus. Therefore, it is crucial to identify other factors or chemical compounds to obtain neurons with high efficiency. In this study we show that the combination of Rarg (retinoic acid receptor ?) and Nr5a2 (nuclear receptor subfamily 5, group A, member 2; also known as Lrh-1 (liver receptor homologue 1)) rapidly promote the iN cell maturation within 1 week and greatly facilitate the conversion with neuronal purities of ?50% and yields of >130%. They also improve neuronal pattern formation, electrophysiological characteristics, and functional integration in vivo. Moreover, the chemical compound agonists to Rarg and Nr5a2 function effectively as well. This approach may be used for the generation and application of iN cells in regenerative medicine.
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Quasi-trapping chemical ionization source based on a commercial VUV lamp for time-of-flight mass spectrometry.
Anal. Chem.
PUBLISHED: 01-17-2014
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The application of VUV lamp-based single photon ionization (SPI) was limited due to low photon energy and poor photon flux density. In this work, we designed a quasi-trapping chemical ionization (QT-CI) source with a commercial VUV 10.6 eV krypton lamp for time-of-flight mass spectrometry. The three electrode configuration ion source with RF voltage on the second electrode constitutes a quasi-trapping region, which has two features: accelerating the photoelectrons originated from the photoelectric effect with VUV light to trigger the chemical ionization through ion-molecule reaction and increasing the collisions between reactant ion O2(+) and analyte molecules to enhance the efficiency of chemical ionization. Compared to single SPI based on VUV krypton lamp, the QT-CI ion source not only apparently improved the sensitivity (e.g., 12-118 fold enhancement were achieved for 13 molecules, including aromatic hydrocarbon, chlorinated hydrocarbon, hydrogen sulfide, etc.) but also extended the range of ionizable molecules with ionization potential (IP) higher than 10.6 eV, such as propane, dichloroethane, and trichloromethane.
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Histopathological features and distribution of EV71 antigens and SCARB2 in human fatal cases and a mouse model of enterovirus 71 infection.
Virus Res.
PUBLISHED: 01-12-2014
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Enterovirus 71 (EV71) is a neurotropic pathogen that causes hand, foot, and mouth disease. While infection is usually self-limiting, a minority of patients infected with EV71 develop severe neurological complications. In humans, EV71 has been reported to utilize the scavenger receptor class B, member 2 (SCARB2) as a receptor for infectious cellular entry. In this study, we define the pathological features of EV71-associated disease as well as the distribution of EV71 antigen and SCARB2 in human fatal cases and a mouse model. Histopathologically, human fatal cases showed severe central nervous system (CNS) changes, mainly in the brainstems, spinal cords, and thalamus. These patient further exhibited pulmonary edema and necrotic enteritis. Immunohistochemical analysis of human fatal cases demonstrated that EV71 antigen and SCARB2 were observed mainly in neurons, microglia cells and inflammatory cells in the CNS, and epithelial cells in the intestines. However, skeletal muscle tissue was negative for EV71 antigen. In a mouse model of EV71 infection, we observed massive necrotic myositis, different degrees of viral diseases in CNS, and extensive interstitial pneumonia. In mice, EV71 exhibits strong myotropism compared to the neurotropism seen in humans. EV71 antigen was detected in the spinal cord and brainstem of mice. However, there was no clear correlation between mouse SCARB2 and EV71 antigen distribution in the mouse model, consistent with previous results that SCARB2 functions as a receptor for EV71 in humans but not mice. The EV71-induced lesions seen in the mouse model resembled the pathological changes seen in human samples. These results increase our understanding of EV71 pathogenesis and will inform further work developing a mouse model for EV71 infection.
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Hepatoid adenocarcinoma of the colon in a patient with inflammatory bowel disease.
World J. Gastroenterol.
PUBLISHED: 01-10-2014
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A case is presented of a 36-year-old male with primary sclerosing cholangitis-associated inflammatory bowel disease (PSC-IBD) and two synchronous stage 1 adenocarcinomata of the colon, who was initially treated with a subtotal colectomy with ileostomy. One year later, the patient presented with extensive intra-abdominal lymphadenopathy and peritoneal carcinomatosis, as well as a markedly elevated serum level of alpha-fetoprotein (AFP). Fine needle aspiration biopsy of a porta hepatis lymph node revealed a metastatic hepatoid adenocarcinoma. Subsequent review of the previous colectomy specimen showed that one of the previously identified adenocarcinomata had features suggestive of a hepatoid colonic adenocarcinoma. The patient was subsequently treated with a cytotoxic regimen of FOLFOX (oxaliplatin, leucovorin, 5-fluorouracil) and bevacizumab, with stable results being achieved after six months. This case presents the first known report of PSC-IBD associated with synchronous typical and hepatoid adenocarcinomata of the colon and highlights the importance of considering hepatoid adenocarcinoma as a differential diagnosis in patients with an increasing serum AFP level.
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Analysis of a urinary biomarker panel for obstructive nephropathy and clinical outcomes.
PLoS ONE
PUBLISHED: 01-01-2014
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To follow up renal function changes in patients with obstructive nephropathy and to evaluate the predictive value of biomarker panel in renal prognosis.
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Prevalence of BRCA1 gene mutation in breast cancer patients in Guangxi, China.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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The prevalence of breast cancer susceptibility gene 1 mutation in breast cancer patients of south China has not been well revealed. This study was to invest the prevalence of BRCA1 gene mutation in breast cancer patients in Guangxi, China, and to try reflecting its relevance in genetic counseling of breast cancer.
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Salicylic Acid Alleviates the Adverse Effects of Salt Stress in Torreya grandis cv. Merrillii Seedlings by Activating Photosynthesis and Enhancing Antioxidant Systems.
PLoS ONE
PUBLISHED: 01-01-2014
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Salt stress is a major factor limiting plant growth and productivity. Salicylic acid (SA) has been shown to ameliorate the adverse effects of environmental stress on plants. To investigate the protective role of SA in ameliorating salt stress on Torreya grandis (T. grandis) trees, a pot experiment was conducted to analyze the biomass, relative water content (RWC), chlorophyll content, net photosynthesis (Pn), gas exchange parameters, relative leakage conductivity (REC), malondialdehyde (MDA) content, and activities of superoxide dismutase (SOD) and peroxidase (POD) of T. grandis under 0.2% and 0.4% NaCl conditions with and without SA.
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Transparent, biocompatible nanostructured surfaces for cancer cell capture and culture.
Int J Nanomedicine
PUBLISHED: 01-01-2014
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Circulating tumor cells (CTCs) in the blood which have detached from both the primary tumor and any metastases may be considered as a "liquid biopsy" and are expected to replace tumor biopsies in the monitoring of treatment response and determining patient prognosis. Here, we introduce a facile and efficient CTC detection material made of hydroxyapatite/chitosan (HA/CTS), which is beneficial because of its transparency and excellent biological compatibility. Atomic force microscopy images show that the roughness of the HA/CTS nanofilm (HA/CTSNF) substrates can be controlled by changing the HA:CTS ratio. Enhanced local topographic interactions between nano-components on cancer cell membranes, and the antibody coated nanostructured substrate lead to improved CTC capture and separation. This remarkable nanostructured substrate has the potential for CTC culture in situ and merits further analysis. CTCs captured from artificial blood samples were observed in culture on HA/CTSNF substrates over a period of 14 days by using conventional staining methods (hematoxylin eosin and Wright's stain). We conclude that these substrates are multifunctional materials capable of isolating and culturing CTCs for subsequent studies.
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Circulating tumor cells (CTCs) detected by RT-PCR and its prognostic role in gastric cancer: a meta-analysis of published literature.
PLoS ONE
PUBLISHED: 01-01-2014
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The prognostic significance of circulating tumor cells (CTCs) is controversial in gastric cancer (GC). We performed a meta-analysis of available studies to assess its prognostic value detected by RT-PCR for patients diagnosed with GC.
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Diversity of two forms of DNA methylation in the brain.
Front Genet
PUBLISHED: 01-01-2014
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DNA methylation 5-methylcytosine (5mC) predicts a compacting chromatin inaccessible to transcription. The discovery of 5-hydroxymethylcytosine (5hmC), which is derived from 5mC, adds a new dimension to the mechanism and role of DNA methylation in epigenetics. Genomic evidence indicates that the 5hmC is located in the alternate regions to 5mC. However, the nature of 5hmC, as compared with classical 5mC remains unclear. Observing the mouse brain through embryonic development to the adult, first, we found that 5hmC is not merely an intermediate metabolite of demethylation, but is long lasting, chromatically distinct, and dynamically changing during neurodevelopment. Second, we found that 5hmC distinctly differs from 5mC in its chromatin affiliation during neural stem cell (NSC) development. Thirdly, we found both 5mC and 5hmC to be uniquely polarized and dynamic through the NSC development. 5mC was found to progressively polarize with MBD1 and MeCP2, and recruits H3K9me3 and H3K27me3; while 5hmC progressively co-localizes with MBD3 and recruits H3K4me2. Critical differential binding of 5mC with MBD1, and 5hmC with MBD3 was validated by Resonance Energy Transfer technique FLIM-FRET. This transition and polarization coincides with neuroprogenitor differentiation. Finally, at the time of synaptogenesis, 5mC gradually accumulates in the heterochromatin while 5hmC accumulates in the euchromatin, which is consistent with the co-localization of 5hmC with PolII, which mediates RNA transcription. Our data indicate that 5mC and 5hmC are diverse in their functional interactions with chromatin. This diversity is likely to contribute to the versatile epigenetic control of transcription mediating brain development and functional maintenance of adult brain.
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Enamelin is critical for ameloblast integrity and enamel ultrastructure formation.
PLoS ONE
PUBLISHED: 01-01-2014
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Mutations in the human enamelin gene cause autosomal dominant hypoplastic amelogenesis imperfecta in which the affected enamel is thin or absent. Study of enamelin knockout NLS-lacZ knockin mice revealed that mineralization along the distal membrane of ameloblast is deficient, resulting in no true enamel formation. To determine the function of enamelin during enamel formation, we characterized the developing teeth of the Enam-/- mice, generated amelogenin-driven enamelin transgenic mouse models, and then introduced enamelin transgenes into the Enam-/- mice to rescue enamel defects. Mice at specific stages of development were subjected to morphologic and structural analysis using ?-galactosidase staining, immunohistochemistry, and transmission and scanning electron microscopy. Enamelin expression was ameloblast-specific. In the absence of enamelin, ameloblasts pathology became evident at the onset of the secretory stage. Although the aggregated ameloblasts generated matrix-containing amelogenin, they were not able to create a well-defined enamel space or produce normal enamel crystals. When enamelin is present at half of the normal quantity, enamel was thinner with enamel rods not as tightly arranged as in wild type suggesting that a specific quantity of enamelin is critical for normal enamel formation. Enamelin dosage effect was further demonstrated in transgenic mouse lines over expressing enamelin. Introducing enamelin transgene at various expression levels into the Enam-/- background did not fully recover enamel formation while a medium expresser in the Enam+/- background did. Too much or too little enamelin abolishes the production of enamel crystals and prism structure. Enamelin is essential for ameloblast integrity and enamel formation.
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What is Visualize?

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.