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Find video protocols related to scientific articles indexed in Pubmed.
Endovascular embolization for managing anastomotic bleeding after stapled digestive tract anastomosis.
Acta Radiol
PUBLISHED: 11-20-2014
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Anastomotic bleeding is an infrequent but life-threatening complication after stapled digestive tract anastomosis. Endovascular embolization is one of the available treatments, but precise clinical outcomes are yet to be evaluated.
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Diversity and distribution of arbuscular mycorrhizal fungi along altitudinal gradients in Mount Taibai of the Qinling Mountains.
Can. J. Microbiol.
PUBLISHED: 11-13-2014
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Elevational patterns of plant and animal diversity have been studied for centuries; however, the effects of land elevation on arbuscular mycorrhizal (AM) fungal diversity remains unclear. We examined AM fungal diversity and distribution along 19 elevation belts in Mount Taibai of the Qinling Mountains, with the aim to assess the altitudinal diversity patterns. In total, 63 AM fungal taxa belonging to 12 genera were discovered. Mycorrhizal colonization rates on roots; AM fungal spore density; and fungal species richness, evenness, and diversity had different patterns in terms of the changes of elevation. Root colonization followed a cubical parabolic pattern, with a peak and a foot at an elevation of about 2000 and 3000 m above sea level, respectively. Species richness decreased monotonically from the lowest to the highest elevations. Spore density and ?-diversity exhibited a unimodal pattern and peaked at an elevation of 2107 and 1350 m, respectively. Species evenness increased monotonically at an elevation of between 1050 and 2250 m. ?-Diversity also presented a basically incremental pattern along altitudinal gradients. Our findings suggest that elevation changes were the main factor governing the patterns of AM fungal diversity.
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Traditional Chinese medication for cardiovascular disease.
Nat Rev Cardiol
PUBLISHED: 11-12-2014
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Traditional Chinese medication (TCM) is increasingly used to treat cardiovascular disease (CVD) in China and some other Asian countries. However, therapeutic efficacy and adverse effects of TCM are difficult to evaluate because few large-scale, randomized controlled trials (RCTs) enrolling patients with CVD have been performed. In this Review, we critically examine the current evidence on the cardiovascular effects of TCM. We reviewed 68 RCTs that included a total of 16,171 patients. The methodological quality of the trials was generally low. Only three reports described adverse cardiovascular events specifically, although in most studies TCM was associated with significant improvements in surrogate end points for hypertension, coronary heart disease, cardiac arrhythmias, and heart failure. The risk of adverse effects was not increased compared with no intervention, placebo, or Western medications. However, whether TCM is effective in reducing the all-cause or cardiovascular mortality in patients with CVD remains unknown and must be tested in large-scale RCTs with adverse cardiovascular events as primary end points.
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Multi-responsive cellulose nanocrystal-rhodamine conjugates: an advanced structure study by solid-state dynamic nuclear polarization (DNP) NMR.
Phys Chem Chem Phys
PUBLISHED: 11-04-2014
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Multi-stimuli responsive materials based on cellulose nanocrystals (CNCs), especially using non-conventional stimuli including light, still need more explorations, to fulfill the requirements of complicated application environments. The structure determination of functional groups on the CNC surface constitutes a significant challenge, partially due to their low amounts. In this study, rhodamine spiroamide groups are immobilized onto the surface of CNCs leading to a hybrid compound being responsive to pH-values, heat and UV light. After the treatment with external stimuli, the fluorescent and correlated optical color change can be induced, which refers to a ring opening and closing process. Amine and amide groups in rhodamine spiroamide play the critical role in this switching process. Solid-state NMR spectroscopy coupled with sensitivity-enhanced dynamic nuclear polarization (DNP) was used to measure (13)C and (15)N in natural abundance, allowing the determination of structural changes during the switching process. It is shown that a temporary bond through an electrostatic interaction could be formed within the confined environment on the CNC surface during the heat treatment. The carboxyl groups on the CNC surface play a pivotal role in stabilizing the open status of rhodamine spiroamide groups.
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Prognostic Value of C-Reactive Protein in Esophageal Cancer: a Meta-analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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The classical inflammatory biomarker, C-reactive protein (CRP), has been identified to be related to progression of esophageal cancer. Some research showed that elevated pretreatment serum CRP indicated a poor prognosis, but results have been inconsistent.
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[The changes of p-Akt/MuRF1/FoxO1 proteins expressions in the conditions of training and immobilization in rats' gastrocnemius muscle].
Sheng Li Xue Bao
PUBLISHED: 10-22-2014
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This study was aimed to investigate the changes of muscle protein synthesis and degradation under different movement conditions, so as to provide theoretical basis for muscle atrophy mechanism. Sprague Dawley (SD) rats were randomly divided into control, endurance training (treadmill training), hind limb overhanging and eccentric training (treadmill training, angle -16º) groups. The gastrocnemius muscles of rats were taken and weighed. The muscle was sectioned, and HE staining was employed to determine the cell's cross-sectional area. Protein expression of p-Akt was measured by immunohistochemistry; and the expressions of MuRF1 and FoxO1 were determined by Western blot. The results showed that, compared with control group, hind limb overhanging and eccentric training groups exhibited decreased muscle weight and cross-sectional area, but endurance training group did not show any changes. The expressions of p-Akt in endurance and eccentric training groups, not in hind limb overhanging group, were significantly higher than that in control group. Compared with that of control, MuRF1 protein remained unchanged in endurance training groups, but was increased in eccentric training and hind limb overhanging groups; FoxO1 protein was decreased in endurance training group, but was increased in eccentric training and hind limb overhanging groups. These results indicate that movement (endurance and eccentric training) can activate Akt expression, but does not increase muscle weight, whereas eccentric training and hind limb overhanging can increase the expressions of MuRF1 and FoxO1, and induce amyotrophy, suggesting MuRF1 and FoxO1 are major determinant factors in muscle atrophy.
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[Results of low-dose computed tomography (LDCT) screening for early lung cancer: prevalence in 4 690 asymptomatic participants].
Zhonghua Zhong Liu Za Zhi
PUBLISHED: 10-21-2014
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To report the results of low-dose computed tomography (LDCT) screening for early lung cancer in 4 690 asymptomatic participants at the Cancer Hospital, Chinese Academy of Medical Sciences between July 2007 and June 2012.
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Down-regulation of GPR137 expression inhibits proliferation of colon cancer cells.
Acta Biochim. Biophys. Sin. (Shanghai)
PUBLISHED: 10-09-2014
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G protein-coupled receptors (GPRs) are highly related to oncogenesis and cancer metastasis. G protein-coupled receptor 137 (GPR137) was initially reported as a novel orphan GPR about 10 years ago. Some orphan GPRs have been implicated in human cancers. The aim of this study is to investigate the role of GPR137 in human colon cancer. Expression levels of GRP137 were analyzed in different colon cancer cell lines by quantitative polymerase chain reaction and western blot analysis. Lentivirus-mediated short hairpin RNA was specifically designed to knock down GPR137 expression in colon cancer cells. Cell viability was measured by methylthiazoletetrazolium and colony formation assays. In addition, cell cycle characteristic was investigated by flow cytometry. GRP137 expression was observed in all seven colon cancer cell lines at different levels. The mRNA and protein levels of GPR137 were down-regulated in both HCT116 and RKO cells after lentivirus infection. Lentivirus-mediated silencing of GPR137 reduced the proliferation rate and colonies numbers. Knockdown of GPR137 in both cell lines led to cell cycle arrest in the G0/G1 phase. These results indicated that GPR137 plays an important role in colon cancer cell proliferation. A better understanding of GPR137's effects on signal transduction pathways in colon cancer cells may provide insights into the novel gene therapy of colon cancer.
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Rational design of signal-on biosensors by using photoinduced electron transfer between Ag nanoclusters and split G-quadruplex halves-hemin complexes.
Chem. Commun. (Camb.)
PUBLISHED: 10-07-2014
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Photoinduced electron transfer (PET) between DNA-Ag nanoclusters (AgNCs) and G-quadruplex halves-hemin has been used for building a new sensing platform for the signal-on detection of adenosine and RNA.
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Sterol biosynthesis is required for heat resistance but not extracellular survival in leishmania.
PLoS Pathog.
PUBLISHED: 10-01-2014
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Sterol biosynthesis is a crucial pathway in eukaryotes leading to the production of cholesterol in animals and various C24-alkyl sterols (ergostane-based sterols) in fungi, plants, and trypanosomatid protozoa. Sterols are important membrane components and precursors for the synthesis of powerful bioactive molecules, including steroid hormones in mammals. Their functions in pathogenic protozoa are not well characterized, which limits the development of sterol synthesis inhibitors as drugs. Here we investigated the role of sterol C14?-demethylase (C14DM) in Leishmania parasites. C14DM is a cytochrome P450 enzyme and the primary target of azole drugs. In Leishmania, genetic or chemical inactivation of C14DM led to a complete loss of ergostane-based sterols and accumulation of 14-methylated sterols. Despite the drastic change in lipid composition, C14DM-null mutants (c14dm(-)) were surprisingly viable and replicative in culture. They did exhibit remarkable defects including increased membrane fluidity, failure to maintain detergent resistant membrane fraction, and hypersensitivity to heat stress. These c14dm(-) mutants showed severely reduced virulence in mice but were highly resistant to itraconazole and amphotericin B, two drugs targeting sterol synthesis. Our findings suggest that the accumulation of toxic sterol intermediates in c14dm(-) causes strong membrane perturbation and significant vulnerability to stress. The new knowledge may help improve the efficacy of current drugs against pathogenic protozoa by exploiting the fitness loss associated with drug resistance.
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Hepatic Hepcidin Protects against Polymicrobial Sepsis in Mice by Regulating Host Iron Status.
Anesthesiology
PUBLISHED: 09-30-2014
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Hepcidin is a master regulator of iron metabolism primarily produced by the liver. Markedly increased hepcidin levels have been observed in septic individuals, while decreased hepatic hepcidin expression has been demonstrated in liver diseases that tend to develop into sepsis. However, the role of liver hepcidin in sepsis remains unknown.
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Connection between the packing efficiency of binary hard spheres and the glass-forming ability of bulk metallic glasses.
Phys Rev E Stat Nonlin Soft Matter Phys
PUBLISHED: 09-29-2014
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We perform molecular dynamics simulations to compress binary hard spheres into jammed packings as a function of the compression rate R, size ratio ?, and number fraction x_{S} of small particles to determine the connection between the glass-forming ability (GFA) and packing efficiency in bulk metallic glasses (BMGs). We define the GFA by measuring the critical compression rate R_{c}, below which jammed hard-sphere packings begin to form "random crystal" structures with defects. We find that for systems with ??0.8 that do not demix, R_{c} decreases strongly with ??_{J}, as R_{c}?exp(-1/??_{J}^{2}), where ??_{J} is the difference between the average packing fraction of the amorphous packings and random crystal structures at R_{c}. Systems with ??0.8 partially demix, which promotes crystallization, but we still find a strong correlation between R_{c} and ??_{J}. We show that known metal-metal BMGs occur in the regions of the ? and x_{S} parameter space with the lowest values of R_{c} for binary hard spheres. Our results emphasize that maximizing GFA in binary systems involves two competing effects: minimizing ? to increase packing efficiency, while maximizing ? to prevent demixing.
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Paip1, an Effective Stimulator of Translation Initiation, Is Targeted by WWP2 for Ubiquitination and Degradation.
Mol. Cell. Biol.
PUBLISHED: 09-29-2014
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Poly(A)-binding protein-interacting protein 1 (Paip1) stimulates translational initiation by inducing the circularization of mRNA. However, the mechanisms underlying Paip1 regulation, particularly its protein stability, are still unclear. Here, we show that the E6AP carboxyl terminus (HECT)-type ubiquitin ligase WW domain-containing protein 2 (WWP2), a homolog of the HECT-type ubiquitin ligase WWP1, interacts with and targets Paip1 for ubiquitination and proteasomal degradation. Mapping of the region including the WW domain of WWP2 revealed the interaction between WWP2 and the PABP-binding motif 2 (PAM2) of Paip1. The two consecutive PXXY motifs in PAM2 are required for WWP2-mediated ubiquitination and degradation. Furthermore, ectopic expression of WWP2 decreases translational stimulatory activity with the degradation of Paip1. We therefore provide evidence that the stability of Paip1 can be regulated by ubiquitin-mediated degradation, thus highlighting the importance of WWP2 as a suppressor of translation.
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Sensitive and selective amplified visual detection of cytokines based on exonuclease III-aided target recycling.
Chem. Commun. (Camb.)
PUBLISHED: 09-18-2014
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A new Exo III assisted strand-cleavage cycle and ligand-responsive quadruplex formation strategy for amplified and label-free detection of IFN-? was reported with a detection limit of 0.1 pM and a visual detection limit of 20 pM by the naked eye.
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[Laws of acupoint selection of prescriptions for treatment of cervicogenic headache by acupuncture: a modern literature research].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 09-17-2014
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To summarize laws of acupoint selection of prescriptions for treatment of cervicogenic headache by acupuncture in modern literature.
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Nanostructured Mn-based oxides for electrochemical energy storage and conversion.
Chem Soc Rev
PUBLISHED: 09-10-2014
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Batteries and supercapacitors as electrochemical energy storage and conversion devices are continuously serving for human life. The electrochemical performance of batteries and supercapacitors depends in large part on the active materials in electrodes. As an important family, Mn-based oxides have shown versatile applications in primary batteries, secondary batteries, metal-air batteries, and pseudocapacitors due to their high activity, high abundance, low price, and environmental friendliness. In order to meet future market demand, it is essential and urgent to make further improvements in energy and power densities of Mn-based electrode materials with the consideration of multiple electron reaction and low molecular weight of the active materials. Meanwhile, nanomaterials are favourable to achieve high performance by means of shortening the ionic diffusion length and providing large surface areas for electrode reactions. This article reviews the recent efforts made to apply nanostructured Mn-based oxides for batteries and pseudocapacitors. The influence of structure, morphology, and composition on electrochemical performance has been systematically summarized. Compared to bulk materials and notable metal catalysts, nanostructured Mn-based oxides can promote the thermodynamics and kinetics of the electrochemical reactions occurring at the solid-liquid or the solid-liquid-gas interface. In particular, nanostructured Mn-based oxides such as one-dimensional MnO2 nanostructures, MnO2-conductive matrix nanocomposites, concentration-gradient structured layered Li-rich Mn-based oxides, porous LiNi0.5Mn1.5O4 nanorods, core-shell structured LiMnSiO4@C nanocomposites, spinel-type Co-Mn-O nanoparticles, and perovskite-type CaMnO3 with micro-nano structures all display superior electrochemical performance. This review should shed light on the sustainable development of advanced batteries and pseudocapacitors with nanostructured Mn-based oxides.
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[The effect of nasal irrigation in the treatment of allergic rhinitis].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-05-2014
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To compare the symptoms and lower airway inflammatory factors of patients with allergic rhinitis (AR), and to observe the effect of nasal irrigation in the treatment of allergic rhinitis.
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High expression of SPHK1 in sacral chordoma and association with patients' poor prognosis.
Med. Oncol.
PUBLISHED: 09-03-2014
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Sacral chordoma is an aggressive bone tumor with a high local recurrence rate. Surgery remains the standard treatment because of its resistance to chemotherapy and radiotherapy. However, recurrence occurs frequently even after complete surgical resection. Great effort has been invested in discovering novel biomarkers and therapeutic targets. To date, the molecular mechanism is still unclear. In this study, we evaluated the expression of sphingosine kinase 1 (SPHK1) in 42 sacral chordoma samples and 16 distant normal tissue specimens by immunohistochemical staining. In addition, we analyzed its association with the clinical factors and patients' prognosis. Of all the chordoma samples, 69 % (29/42) showed high expression of SPHK1, whereas, only 19 % (3/16) of distant normal tissues expressed a high level of SPHK1 (p = 0.001). Chi-square analysis revealed that high expression of SPHK1 was significantly correlated with tumor recurrence (p = 0.019) and invasion into surrounding muscle (p = 0.005), while the data did not indicate any association with patients' gender, age, tumor location and size (p > 0.05). Kaplan-Meier survival curve and log-rank test showed that patients with high expression of SPHK1 possessed shorter continuous disease-free survival time. Conclusively, SPHK1 may become a potential biomarker for sacral chordoma in predicting its recurrence and patients' prognosis.
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An in vitro and in vivo comparison of solid and liquid-oil cores in transdermal aconitine nanocarriers.
J Pharm Sci
PUBLISHED: 09-03-2014
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This study compared transdermal aconitine delivery using solid lipid nanoparticles (SLN) and microemulsion (ME) vehicles. Aconitine-loaded SLN and ME were formulated with the same surfactant, cosurfactant, and water content, with an equal amount of oil matrix (ATO 888 for SLN and ethyl oleate for ME). These nanosized formulations (70-90 nm) showed suitable pH values and satisfactory skin tissue biocompatibility. SLN contained a higher concentration of smaller nanoparticles, compared with that in ME. Neither of the nanocarriers penetrated across excised skin in their intact form. In vitro transdermal delivery studies found that transdermal aconitine flux was lower from SLN than from ME (p < 0.05), but skin aconitine deposition was higher using SLN (p < 0.05). Fluorescence-activated cell sorting indicated that in vitro uptake of fluorescently labeled SLN by human immortalized keratinocyte (HaCaT) cells was greater than that of ME, indicating that a transcellular pathway may contribute to cutaneous drug absorption more effectively from SLN. In vivo studies found that these formulations could loosen stratum corneum layers and increase skin surface crannies, which may also enhance transdermal aconitine delivery. SLN produced a more sustained aconitine release, indicating that compared with ME, this transdermal delivery vehicle may reduce the toxicity of this drug. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:3602-3610, 2014.
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Functional neuroimaging of acute oculomotor deficits in concussed athletes.
Brain Imaging Behav
PUBLISHED: 09-02-2014
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In the pursuit to better understand the neural underpinnings of oculomotor deficits following concussion we performed a battery of oculomotor tests while performing simultaneous functional magnetic resonance imaging (fMRI). Based on the increasing evidence that concussion can disrupt multiple brain functional networks, including the oculomotor control networks, a series of classic saccadic and smooth pursuit tasks were implemented. Nine concussed athletes were tested within seven days of injury along with nine age and sex matched healthy normal volunteers. Both behavioral and fMRI data revealed differential results between the concussed and normal volunteer groups. Concussed subjects displayed longer latency time in the saccadic tasks, worse position errors, and fewer numbers of self-paced saccades compared to normal volunteer subjects. Furthermore, the concussed group showed recruitment of additional brain regions and larger activation sites as evidenced by fMRI. As a potential diagnostic and management tool for concussion, oculomotor testing shows promise, and here we try to understand the reasons for this disrupted performance with the aide of advanced neuroimaging tools.
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Determining mycotoxins in baby foods and animal feeds using stable isotope dilution and liquid chromatography tandem mass spectrometry.
J. Agric. Food Chem.
PUBLISHED: 09-02-2014
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We developed a stable isotope dilution assay with liquid chromatography tandem mass spectrometry (LC-MS/MS) to determine multiple mycotoxins in baby foods and animal feeds. Samples were fortified with [(13)C]-uniformly labeled mycotoxins as internal standards ([(13)C]-IS) and prepared by solvent extraction (50% acetonitrile in water) and filtration, followed by LC-MS/MS analysis. Mycotoxins in each sample were quantitated with the corresponding [(13)C]-IS. In general, recoveries of aflatoxins (2-100 ng/g), deoxynivalenol, fumonisins (50-2000 ng/g), ochratoxin A (20-1000 ng/kg), T-2 toxin, and zearalenone (40-2000 ng/g) in tested matrices (grain/rice/oatmeal-based formula, animal feed, dry cat/dog food) ranged from 70 to 120% with relative standard deviations (RSDs) <20%. The method provides sufficient selectivity, sensitivity, accuracy, and reproducibility to screen for aflatoxins at ng/g concentrations and deoxynivalenol and fumonisins at low ?g/g concentrations in baby foods and animal feeds, without using conventional standard addition or matrix-matched calibration standards to correct for matrix effects.
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Rhizotomy targeting the intermediate nerve, the glossopharyngeal nerve and the upper 1st to 2nd rootlets of the vagus nerve for the treatment of laryngeal neuralgia combined with intermediate nerve neuralgia--a case report.
BMC Surg
PUBLISHED: 08-28-2014
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In neurosurgery, the most common type of facial and pharyngeal pain is trigeminal neuralgia. In contrast, glossopharyngeal neuralgia is relatively rare, and laryngeal neuralgia is the most rarely observed.
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The interaction of APEX1 variant with polycyclic aromatic hydrocarbons on increasing chromosome damage and lung cancer risk among male Chinese.
Mol. Carcinog.
PUBLISHED: 08-22-2014
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Polycyclic aromatic hydrocarbons (PAHs) are the most significant contributors to tobacco-induced lung carcinogenesis. Apurinic/apyrimidinic endonuclease 1 (APE1) is a central enzyme in the removal of apurinic/apyrimidinic sites caused by DNA damaging agents. This study aimed to investigate the potential interaction of APEX1 polymorphisms and PAHs on genetic damage and lung cancer risk among male Chinese. We recruited an occupational cohort of 922 male coke oven workers and determined their DNA damage levels by calculating the lymphocytic micronucleus (MN) frequencies. Two well-studied APEX1 polymorphisms (-307A?>?C and Asp148Glu) and their associations with MN frequencies were examined. The impact of MN-related single nucleotide polymorphism (SNP) on lung cancer risk was further investigated in two case-control studies including 1634 male lung cancer patients and 1678 controls. It was shown that, the APEX1 148Glu allele was associated with significantly higher MN frequencies than 148Asp allele, with strongest associations among the highest PAH-exposure workers (P?=?0.008). The APEX1 148Glu allele was also associated with increased lung cancer risk among male smokers, especially among heavy smokers in both case-control studies (odd ratio: 4.40, 95%CI: 3.29-5.72). In addition, APEX1 148Glu variant interacts with smoking in increasing male lung cancer risk, as measured by the attributable proportion due to interaction, which was 0.23 (95%CI: 0.06-0.39). This study showed evidence on interaction between APEX1 148Glu variant and cigarette smoking in increasing lung cancer susceptibility among male Chinese, which may be due to the synergistic effects of APEX1 148Glu and PAHs in increasing chromosome damage levels. The results provide a new insight into gene-interactions in lung carcinogenesis. © 2014 Wiley Periodicals, Inc.
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Chinese urologists' practice patterns of diagnosing and treating chronic pelvic pain syndrome: a questionnaire survey.
Beijing Da Xue Xue Bao
PUBLISHED: 08-19-2014
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To investigate the application of the Chinese Urological Association (CUA) guidelines on prostatitis and the effects on the clinical practice patterns of diagnosing and treating chronic pelvic pain syndrome (CPPS) among Chinese urologists.
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Neo-Fused Hexaphyrin: A Molecular Puzzle Containing an N-Linked Pentaphyrin.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-15-2014
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The first neo-confused hexaphyrin(1.1.1.1.1.0) was synthesized by oxidative ring closure of a hexapyrrane bearing two terminal "confused" pyrroles. The new compound displays a folded conformation with a short interpyrrolic C???N distance of 3.102 Å, and thus it readily underwent ring fusion to afford a neo-fused hexaphyrin with an unprecedented 5,5,5,7-tetracyclic ring structure. Furthermore, coordination of Cu(II) triggered a ring opening/contracting reaction to afford a Cu(II) complex of an N-linked pentaphyrin derivative. The roles of reactive N?C bonds in the porphyrinoid macrocycles were demonstrated.
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Neuroprotective properties of ciliary neurotrophic factor on retinoic acid (RA)-predifferentiated SH-SY5Y neuroblastoma cells.
Folia Neuropathol
PUBLISHED: 08-15-2014
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Ciliary neurotrophic factor (CNTF) is a neurocytokine, which could promote survival and/or differentiation in many cell types. In this study, the biological effects of CNTF on retinoic acid (RA)-predifferentiated SH-SY5Y neuroblastoma cells and the underlying molecular mechanism of this effect were investigated for the first time. The results showed that RA was able to increase cells susceptibility to CNTF via regulating the expression levels of CNTF receptors. A further study revealed that CNTF could induce phosphorylation of STAT3, Akt and ERK1/2 in RA-predifferentiated SH-SY5Y neuroblastoma cells, while the promoting activity of CNTF on survival and neurite growth of cells was attenuated by co-treatment with JAK2 inhibitor AG490 (25 ?M), STAT3 inhibitor Curcumin (50 ?M), PI3K inhibitor LY-294002 (50 µM), but not by co-treatment with MEK inhibitor PD98059 (50 ?M). These findings suggested that JAK2/STAT3, as well as PI3K/Akt, play important roles in mediating the survival and neurite growth response of RA-predifferentiated cells to CNTF. Our study may be useful to further understand the functional role of CNTF and offer a convenient model to explore the therapeutic potential of CNTF in neurodegenerative diseases.
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Potassium-sulfur batteries: a new member of room-temperature rechargeable metal-sulfur batteries.
Inorg Chem
PUBLISHED: 08-13-2014
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We report room-temperature rechargeable potassium-sulfur (K-S) batteries using ordered mesoporous carbon (CMK-3)/sulfur and polyanilime (PANI) coated CMK-3/sulfur composites as the cathode and metallic potassium as the anode. The electrochemical reaction mechanism was investigated by electrochemical tests, TEM, XRD, and Raman spectra. It was found that K-S batteries delivered two reduction peaks located at about 2.1 and 1.8 V and one oxidation peak at about 2.2 V, respectively. Meanwhile, K2S3 was the major discharge product that could be charged to reversibly form S and K ion. Through optimization of sulfur content, the CMK-3/sulfur composite with 40.8 wt % S displayed an initial discharge capacity of 512.7 mAh g(-1) and a capacity of 202.3 mAh g(-1) after 50 cycles at a current density of 50 mA g(-1). A coating of conductive polyanilime (PANI) on the CMK-3/sulfur composite is effective in enhancing the cycling performance. In comparison, PANI@CMK-3/sulfur composite showed a capacity of 329.3 mAh g(-1) after 50 cycles at 50 mA g(-1). The results shed light on the basic study of rechargeable K-S batteries.
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MoS2 Nanoflowers with Expanded Interlayers as High-Performance Anodes for Sodium-Ion Batteries.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-03-2014
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MoS2 nanoflowers with expanded interlayer spacing of the (002) plane were synthesized and used as high-performance anode in Na-ion batteries. By controlling the cut-off voltage to the range of 0.4-3?V, an intercalation mechanism rather than a conversion reaction is taking place. The MoS2 nanoflower electrode shows high discharge capacities of 350?mAh?g(-1) at 0.05?A?g(-1) , 300?mAh?g(-1) at 1?A?g(-1) , and 195?mAh?g(-1) at 10?A?g(-1) . An initial capacity increase with cycling is caused by peeling off MoS2 layers, which produces more active sites for Na(+) storage. The stripping of MoS2 layers occurring in charge/discharge cycling contributes to the enhanced kinetics and low energy barrier for the intercalation of Na(+) ions. The electrochemical reaction is mainly controlled by the capacitive process, which facilitates the high-rate capability. Therefore, MoS2 nanoflowers with expanded interlayers hold promise for rechargeable Na-ion batteries.
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Screening multimycotoxins in food-grade gums by stable isotope dilution and liquid chromatography/tandem mass spectrometry.
J AOAC Int
PUBLISHED: 07-24-2014
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Stable isotope dilution with LC/MSIMS was used to determine the following 11 mycotoxins in food grade gums: aflatoxins B1, B2, G1, and G2; deoxynivalenol; fumonisins B1, B2, and B3; ochratoxin A; T-2 toxin; and zearalenone. Samples were fortified with 11 [13C]-uniformly labeled internal standard ([13C]-IS) mycotoxins that corresponded to the 11 target mycotoxins and extracted by acetonitrile-water (4 + 1, v/v), followed by LC/MS/MS analysis. Mycotoxins were quantitated with the fortified [13C]-IS in each sample. The average recoveries of aflatoxins B1, B2, G1, and G2 (1, 5, and 25 microg/kg); deoxynivalenol and fumonisins B1, B2, and B3 (25, 100, and 500 microg/kg); and ochratoxin A, T-2 toxin, and zearalenone (10, 50, and 250 microg/kg) ranged from 84 to 117% with RSDs less than 20%. Method-dependent LOQs were from 0.1 (aflatoxin B1) to 25 microg/kg (fumonisin B3). Among 20 market samples, aflatoxin B1 (< LOQ) was detected in a Guar gum and a Tragacanth gum, and zearalenone (6 +/- 0.6 microg/kg) was detected in a Xanthan gum. The detected mycotoxins were further confirmed by comparing their enhanced product ion spectra to those of reference standards. The single laboratory validated stable isotope dilution and LC/MSIMS method provides sufficient selectivity, sensitivity, accuracy, and reproducibility with a simple sample preparation to screen the 11 mycotoxins in gums.
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Hand-held and integrated single-cell pipettes.
J. Am. Chem. Soc.
PUBLISHED: 07-24-2014
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Successful single-cell isolation is a primary step for subsequent chemical and biological analyses of single cells. Conventional single-cell isolation methods often encounter operational complexity, limited efficiency, deterioration of cell viability, incompetence in the isolation of a single-cell into nanoliter liquid, and/or inability to select single adherent cells with specific phenotypes. Here, we develop a hand-held single-cell pipet (hSCP) that is rapid, operationally simple, highly efficient, and inexpensive for unbiased isolation of single viable suspended cells directly from submicroliter cell suspensions into nanoliter droplets without the assistance of any additional equipment. An integrated SCP (iSCP) has also been developed for selective isolation of single suspended and adherent cells according to the fluorescence imaging and morphological features. The isolated single cells can be conveniently transferred into standard 96-/384-well plates, Petri dishes, or vials for cloning, PCR, and other single-cell biochemical assays.
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Clinical curative effect analysis and predictors of prognosis in patients with temporal lobe epilepsy after anterior temporal lobectomy: results after five years.
Chin. Med. J.
PUBLISHED: 07-22-2014
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Anterior temporal lobectomy (ATL) is the most common surgical treatment for temporal lobe epilepsy (TLE), although long-term prognosis is often less favorable than short-term outcomes. This study aimed to examine the outcomes of patients with TLE 5 years after undergoing ATL, and to seek possible predictors of prognosis.
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Lighting up FGFR signaling.
Chem. Biol.
PUBLISHED: 07-19-2014
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In this issue of Chemistry & Biology, Kim and colleagues describe their work on optogenetic control of fibroblast growth factor receptor (FGFR) signaling. By engineering a chimeric receptor, the authors demonstrate that FGFR intracellular signaling can be controlled in space and time by blue light.
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Acquisition of radioresistance in docetaxel-resistant human lung adenocarcinoma cells is linked with dysregulation of miR-451/c-Myc-survivin/rad-51 signaling.
Oncotarget
PUBLISHED: 07-16-2014
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Chemoresistant tumors usually fail to respond to radiotherapy. However, the mechanisms involved in chemo- and radiotherapy cross resistance are not fully understood. Previously, we have identified microRNA (miR)-451 as a tumor suppressor in lung adenocarcinoma (LAD). However, whether miR-451 plays critical roles in chemo- and radiotherapy cross resistance in LAD is unclear. Here, we established two docetaxel-resistant LAD cell models (SPC-A1/DTX and H1299/DTX), and showed that miR-451 was significantly downregulated in docetaxel-resistant LAD cells. Gain - and loss - of - function assays indicated that re-expression of miR-451 could reverse radioresistance of docetaxel-resistant LAD cells both in vitro and in vivo through promoting apoptosis and DNA double-strand breaks (DSBs). The proto-oncogene c-Myc was identified as a direct target of miR-451, and re-expression of miR-451 inhibited survivin and rad-51 expression by reducing the amount of c-Myc protein binding to their promoters. Silencing of c-Myc could phenocopy the effects of miR-451 upregulation, and restoration of c-Myc could partially rescue the effect of miR-451 upregulation on radiosensitivity of docetaxel-resistant LAD cells. Therefore, dysregulation of miR-451/c-Myc-survivin/rad-51 signaling is responsible for radioresistance of docetaxel-resistant LAD cells, and targeting it will be a potential strategy for reversing chemo- and radiotherapy cross resistance of LAD patients.
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Regulatory T cells prevent angiotensin II-induced abdominal aortic aneurysm in apolipoprotein E knockout mice.
Hypertension
PUBLISHED: 07-14-2014
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To test the hypothesis that adoptive transfer of regulatory T cells (Tregs) may dose-dependently inhibit the formation of angiotensin II-induced abdominal aortic aneurysm in apolipoprotein E knockout mice, we established an animal model of abdominal aortic aneurysm by angiotensin II infusion in apolipoprotein E knockout mice. Then mice received different treatment with PBS, low-dose Tregs, high-dose Tregs, or CD25-depleting PC61 antibody. Histopathologic analysis showed that the incidence of abdominal aortic aneurysm was 80%, 76%, 27%, and 71% in the PBS, low-dose Tregs, high-dose Tregs, and PC61 groups, respectively. Tregs treatment markedly decreased macrophage and CD4+ T-cell infiltration and preserved the medial smooth muscle cells. Furthermore, Tregs decreased the levels of proinflammatory cytokines, matrix metalloproteinase-2 (MMP-2) and MMP-9, increased the expression of anti-inflammatory interleukin-10 and transforming growth factor-?, and suppressed apoptosis and oxidative stress. In vitro, Tregs inhibited the response of human aortic smooth muscle cells to angiotensin II and reduced the expression of proinflammatory cytokines, MMP-2 and MMP-9, possibly by inhibiting the activation of nuclear factor-?B and extracellular signal-regulate kinase 1/2. In addition, Tregs downregulated macrophage type 1-related genes and upregulated macrophage type 2-related genes. However, Tregs-mediated effects were largely reversed by disrupting cell-cell contact or using neutralizing antibodies against interleukin-10 and transforming growth factor-?. Adoptive transfer of Tregs dose-dependently prevents angiotensin II-induced abdominal aortic aneurysm in apolipoprotein E knockout mice. The mechanisms may involve declined proinflammatory cytokine expression and MMP-2 and MMP-9 levels and enhanced anti-inflammatory cytokine expression, which is mediated by direct cell-cell contact and soluble mediators.
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Fabrication of porous titanium scaffolds by stack sintering of microporous titanium spheres produced with centrifugal granulation technology.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 07-11-2014
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Microporosity plays a key role in bioactivity and osteoinductivity of a biomaterial scaffold. A simple new approach to fabricating load-bearing porous titanium (Ti) scaffolds with uniform porous structure, highly controllable pore size and excellent biocompatibility was developed in the present study. This method was based on stack sintering of microporous Ti spheres produced with centrifugal granulation of commercial Ti powders. Macropores (180.0-341.8 ?m) and micropores (6.1-11.8 ?m) of the scaffolds were dependent on the sizes of the Ti spheres and the Ti powders, respectively. The compressive strength of the scaffolds (83.4-108.9 MPa) was high enough for the repair of load-bearing bone defects. Besides, the abundant micropores occurred on the rough and convex surface of the Ti spheres in the scaffolds were more favorable for adsorption of serum proteins, and thus promoted the growth of mesenchymal stem cells (MSCs).
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Functionalized nanostructures for enhanced photocatalytic performance under solar light.
Beilstein J Nanotechnol
PUBLISHED: 07-09-2014
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Photocatalytic hydrogen production from water has been considered to be one of the most promising solar-to-hydrogen conversion technologies. In the last decade, various functionalized nanostructures were designed to address the primary requirements for an efficient photocatalytic generation of hydrogen by using solar energy: visible-light activity, chemical stability, appropriate band-edge characteristics, and potential for low-cost fabrication. Our aim is to present a short review of our recent attempts that center on the above requirements. We begin with a brief introduction of photocatalysts coupling two or more semiconductors, followed by a further discussion of the heterostructures with improved matching of both band structures and crystal lattices. We then elaborate on the heterostructure design of the targeted materials from macroscopic regulation of compositions and phases, to the more precise control at the nanoscale, i.e., materials with the same compositions but different phases with certain band alignment. We conclude this review with perspectives on nanostructure design that might direct future research of this technology.
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Oncolytic adenovirus-expressed RNA interference of O(6)-methylguanine DNA methyltransferase activity may enhance the antitumor effects of temozolomide.
Oncol Lett
PUBLISHED: 07-08-2014
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Temozolomide (TMZ) is an example of an alkylating agent, which are known to be effective anticancer drugs for the treatment of various solid tumors, including glioma and melanoma. TMZ acts predominantly through the mutagenic product O(6)-methylguanine, a cytotoxic DNA lesion. The DNA repair enzyme, O(6)-methylguanine DNA methyltransferase (MGMT), which functions in the resistance of cancers to TMZ, can repair this damage. RNA interference (RNAi) has been previously shown to be a potent tool for the knockdown of genes, and has potential for use in cancer treatment. Oncolytic adenoviruses not only have the ability to destroy cancer cells, but may also be possible vectors for the expression of therapeutic genes. We therefore hypothesized that the oncolytic virus-mediated RNAi of MGMT activity may enhance the antitumor effect of TMZ and provide a promising method for cancer therapy.
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Binding-induced and label-free colorimetric method for protein detection based on autonomous assembly of hemin/G-quadruplex DNAzyme amplification strategy.
Biosens Bioelectron
PUBLISHED: 07-07-2014
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In this work, a new binding-induced and label-free colorimetric method for protein detection has been developed on the basis of an autonomous assembly of hemin/G-quadruplex DNAzyme amplification strategy. The system consists of two proximity probes carrying two aptamer sequences as recognition elements for target, and two hairpin structures include three-fourths and one-fourth of the G-quadruplex sequences in inactive configuration as functional elements. In the presence of target protein, two proximity probes bind to the protein simultaneously, forming a stable DNA-protein complex. Then the complex triggers an autonomous cross-opening of the two functional hairpin structures, leading to the formation of numerous hemin/G-quadruplex DNAzymes. The resulting DNAzymes catalyze the oxidation of colorless 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(2-)) to the green-colored ABTS(•-) with the presence of H2O2, thus providing the amplified colorimetric detection of target. Using human ?-thrombin as the protein target, this binding-induced DNAzyme amplification colorimetric method affords high sensitivity with a detection limit of 1.9pM. Furthermore, this method might be further extended to sensitive detection of other proteins by simply replacing recognition elements of proximity probes.
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Comparative analysis of histone H3 and H4 post-translational modifications of esophageal squamous cell carcinoma with different invasive capabilities.
J Proteomics
PUBLISHED: 07-01-2014
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Eukaryotic DNA is packaged into a chromatin with the help of four core histones (H2A, H2B, H3, and H4). Diverse histone post-translational modifications (PTMs) are hence involved in the regulation of gene transcription. However, how this regulation does work is still poorly understood and lacks details. Here we used the mass spectrometry-based proteomics approach to perform a comparative analysis of histone marks at a global level in two phenotypes of esophageal squamous cell carcinoma (ESCC) with different invasiveness. We obtained a comprehensive profiling of histone H3 and H4 PTMs including lysine methylation, acetylation and novel butyrylation. The correlation between histone marks and cancer invasive capabilities was further characterized and one distinguishable PTM, H4K79me2 was discovered and verified in this study. Immunohistochemistry analysis suggests that abnormal level of H4K79me2 may be related to poor survival of ESCC patients. Our results enrich the dataset of the feature pattern of global histone PTMs in ESCC cell lines.
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Mechanisms of Cu2+ migration, recovery and detoxification in Cu2+-, SO4(2-) -containing wastewater treatment process with anaerobic granular sludge.
Environ Technol
PUBLISHED: 06-25-2014
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In this study, anaerobic granular sludge with sulphate-reducing bacteria (SRB) was applied to treat Cu2+-, SO4(2-) -containing wastewater in an expanded granular sludge bed reactor. The migration and enrichment of copper in anaerobic granular sludge were envaluated. By analysing the sludge with X-ray diffraction, copper was determined to be present as covellite (CuS) in the sludge. Observations at the microscopic level showed that CuS precipitates were absorbed onto granules and gradually migrated from the outer to the interior layer of the granule over time and finally accumulated in the core of the granular sludge. Because of the migration of the CuS precipitates and the protection of the extracellular polymeric substances matrix, SRB were able to tolerate copper concentrations up to 10 mg/L. A copper removal efficiency of about 96% was observed at a steady state for 3 months, and copper was enriched in the granular sludge.
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Highly efficient inverted polymer solar cells based on a cross-linkable water-/alcohol-soluble conjugated polymer interlayer.
ACS Appl Mater Interfaces
PUBLISHED: 06-24-2014
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A cross-linkable water/alcohol soluble conjugated polymer (WSCP) material poly[9,9-bis(6'-(N,N-diethylamino)propyl)-fluorene-alt-9,9-bis(3-ethyl(oxetane-3-ethyloxy)-hexyl) fluorene] (PFN-OX) was designed. The cross-linkable nature of PFN-OX is good for fabricating inverted polymer solar cells (PSCs) with well-defined interface and investigating the detailed working mechanism of high-efficiency inverted PSCs based on poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2-b:4,5-b']dithio-phene-2,6-diyl-alt-ethylhexyl-3-fluorothithieno[3,4-b]thiophene-2-carboxylate-4,6-diyl] (PTB7) and (6,6)-phenyl-C71-butyric acid methyl ester (PC71BM) blend active layer. The detailed working mechanism of WSCP materials in high-efficiency PSCs were studied and can be summarized into the following three effects: a) PFN-OX tunes cathode work function to enhance open-circuit voltage (Voc); b) PFN-OX dopes PC71BM at interface to facilitate electron extraction; and c) PFN-OX extracts electrons and blocks holes to enhance fill factor (FF). On the basis of this understanding, the hole-blocking function of the PFN-OX interlayer was further improved with addition of a ZnO layer between ITO and PFN-OX, which led to inverted PSCs with a power conversion efficiency of 9.28% and fill factor high up to 74.4%.
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Long non-coding RNAs in non-small cell lung cancer as biomarkers and therapeutic targets.
J. Cell. Mol. Med.
PUBLISHED: 06-19-2014
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Lung cancer-associated mortality is the most common cause of cancer death worldwide. Non-coding RNAs (ncRNAs), with no protein-coding ability, have multiple biological roles. Long non-coding RNAs (lncRNAs) are a recently characterized class of ncRNAs that are over 200 nucleotides in length. Many lncRNAs have the ability of facilitating or inhibiting the development and progression of tumours, including non-small cell lung cancer (NSCLC). Because of their fundamental roles in regulating gene expression, along with their involvement in the biological mechanisms underlying tumourigenesis, they are a promising class of tissue- and/or blood-based cancer biomarkers. In this review, we highlight the emerging roles of lncRNAs in NSCLC, and discuss their potential clinical applications as diagnostic and prognostic markers and as therapeutic targets.
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A series of blue supramolecular polymers with different counterions for polymer light-emitting diodes.
Chem. Commun. (Camb.)
PUBLISHED: 06-17-2014
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A series of blue supramolecular polymers with different counterions based on host-guest interactions were developed for polymer light-emitting diodes. It was found that the counterions play important roles in the resulting materials' supramolecular interactions as well as the device performance.
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Angiotensin(1-7) attenuates the progression of streptozotocin-induced diabetic renal injury better than angiotensin receptor blockade.
Kidney Int.
PUBLISHED: 06-16-2014
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To explore the potential therapeutic effects of angiotensin(1-7) (Ang(1-7)), an endogenous ligand of the Mas receptor, on streptozotocin-induced diabetic nephropathy, male Wistar rats were randomly divided into two groups: a control group and a diabetic model group. After 12 weeks, the diabetic rats were divided into subgroups for 4-week treatments consisting of no-treatment group, small-, moderate-, and large-dose Ang(1-7) groups, a valsartan group, a large-dose Ang(1-7) plus valsartan group, and an A779 (antagonist of the Mas receptor) group, each with 15 rats. Ang(1-7) improved renal function, attenuated glomeruli sclerosis, oxidative stress, and cell proliferation, decreased the expression of collagen IV, TGF-?1, VEGF, NOX4, p47phox, PKC?, and PKC?1, and the phosphorylation of Smad3. In the rat mesangial HBZY-1 cell line, Ang(1-7) decreased high-glucose-induced oxidative stress, the proliferation and expression of NOX4, p47phox, and TGF-?1, the phosphorylation of Smad3, collagen IV, and VEGF, and the membrane translocation of PKC? and PKC?1. A779 blocked the effects of Ang(1-7) both in vivo and in vitro. The effects of large-dose Ang(1-7) alone and in combination with valsartan were superior to valsartan alone, but the combination had no significant synergistic effect compared with Ang(1-7) alone. Thus, Ang(1-7) ameliorated streptozotocin-induced diabetic renal injury. Large-dose treatment was superior to valsartan in reducing oxidative stress and inhibiting TGF?1/Smad3- and VEGF-mediated pathways.Kidney International advance online publication, 30 July 2014; doi:10.1038/ki.2014.274.
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A PH Domain in ACAP1 Possesses Key Features of the BAR Domain in Promoting Membrane Curvature.
Dev. Cell
PUBLISHED: 06-10-2014
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The BAR (Bin-Amphiphysin-Rvs) domain undergoes dimerization to produce a curved protein structure, which superimposes onto membrane through electrostatic interactions to sense and impart membrane curvature. In some cases, a BAR domain also possesses an amphipathic helix that inserts into the membrane to induce curvature. ACAP1 (Arfgap with Coil coil, Ankyrin repeat, and PH domain protein 1) contains a BAR domain. Here, we show that this BAR domain can neither bind membrane nor impart curvature, but instead requires a neighboring PH (Pleckstrin Homology) domain to achieve these functions. Specific residues within the PH domain are responsible for both membrane binding and curvature generation. The BAR domain adjacent to the PH domain instead interacts with the BAR domains of neighboring ACAP1 proteins to enable clustering at the membrane. Thus, we have uncovered the molecular basis for an unexpected and unconventional collaboration between PH and BAR domains in membrane bending.
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High-efficiency all-polymer solar cells based on a pair of crystalline low-bandgap polymers.
Adv. Mater. Weinheim
PUBLISHED: 06-03-2014
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All-polymer solar cells based on a pair of crystalline low-bandgap polymers (NT and N2200) are demonstrated to achieve a high short-circuit current density of 11.5 mA cm-2 and a power conversion efficiency of up to 5.0% under the standard AM1.5G spectrum with one sun intensity. The high performance of these NT:N2200-based cells can be attributed to the low optical bandgaps of the polymers and the reasonably high and balanced electron and hole mobilities of the NT:N2200 blends due to the crystalline nature of the two polymers.
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Grafting printing of cellulose fabric with the reactive disperse dyes containing N-substituted 3-chloro-2-hydroxypropyl group.
Carbohydr Polym
PUBLISHED: 06-02-2014
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The printed cellulose and its blend materials have wide applications in many high-tech fields. Six new reactive disperse dyes (D1-D6) containing a 3-chloro-2-hydroxypropyl group based on epichlorohydrin were designed and synthesized. The electronic absorption spectra and their grafting printing property for cotton fabrics were investigated. The grafting mechanism on cotton fabric was also discussed. The results show that these dyes had larger bathochromic shifts in stronger polar solvent, dimethylformamide, than in the weaker polar solvents, acetonitrile and acetone. 3-Chloro-2-hydroxypropyl functional group of the dyes could form covalent bond with the hydroxyl group on cellulose by a nucleophilic substituted reaction. The good color yields of D1-D6 on printed cotton fabric were obtained by curing at 170-180 °C. The reactive disperse dyes for printing cellulose fabric had good building up and better printing property. The light fastness, rubbing fastness and fastness to perspiration of the printed fabric were good. The reactive disperse dyes have potential application in cleaner production of printing cotton and cotton/polyester blend fabrics.
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The 2011 heat wave in Greater Houston: Effects of land use on temperature.
Environ. Res.
PUBLISHED: 05-31-2014
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Effects of land use on temperatures during severe heat waves have been rarely studied. This paper examines land use-temperature associations during the 2011 heat wave in Greater Houston. We obtained high resolution of satellite-derived land use data from the US National Land Cover Database, and temperature observations at 138 weather stations from Weather Underground, Inc (WU) during the August of 2011, which was the hottest month in Houston since 1889. Land use regression and quantile regression methods were applied to the monthly averages of daily maximum/mean/minimum temperatures and 114 land use-related predictors. Although selected variables vary with temperature metric, distance to the coastline consistently appears among all models. Other variables are generally related to high developed intensity, open water or wetlands. In addition, our quantile regression analysis shows that distance to the coastline and high developed intensity areas have larger impacts on daily average temperatures at higher quantiles, and open water area has greater impacts on daily minimum temperatures at lower quantiles. By utilizing both land use regression and quantile regression on a recent heat wave in one of the largest US metropolitan areas, this paper provides a new perspective on the impacts of land use on temperatures. Our models can provide estimates of heat exposures for epidemiological studies, and our findings can be combined with demographic variables, air conditioning and relevant diseases information to identify 'hot spots' of population vulnerability for public health interventions to reduce heat-related health effects during heat waves.
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Curcumin Inhibits the Proliferation and Invasiveness of MHCC97-H Cells via p38 Signaling Pathway.
Drug Dev. Res.
PUBLISHED: 05-26-2014
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Preclinical Research Curcumin has been reported to be effective as a cancer therapy. However, the anti-metastatic effect and molecular mechanism(s) of curcumin in hepatocellular carcinoma (HCC) remain poorly understood. The purpose of this study was to test the effects of curcumin on HCC and its putative mechanism(s). Curcumin inhibited the proliferation of HCC cells and inhibited the migration and invasion of these cells at sub-cytotoxic concentrations. Curcumin also decreased the expression and activity of matrix metalloproteinases (MMP)-2 and MMP-9, and reduced p38 phosphorylation. Combination treatment of HCC cells with curcumin and SB203580 (a p38 signaling pathway inhibitor), generated a synergistic effect on the expression of MMP-2 and MMP-9, suggesting that the anti-metastatic effect of curcumin on HCC may involve a p38 signaling pathway.
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Ultrasmall Li2S nanoparticles anchored in graphene nanosheets for high-energy lithium-ion batteries.
Sci Rep
PUBLISHED: 05-14-2014
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Li2S has a high theoretical capacity of 1166 mAh g(-1), but it suffers from limited rate and cycling performance. Herein we reported in-situ synthesis of thermally exfoliated graphene-Li2S (in-situ TG-Li2S) nanocomposite and its application as a superior cathode material alternative to sulfur. Li2S nanoparticles with the size of ~8.5 nm homogeneously anchored in graphene nanosheets were prepared via chemical reduction of pre-sublimed sulfur by lithium triethylborohydride (LiEt3BH). The in-situ TG-Li2S nanocomposite exhibited an initial capacity of 1119 mAh g(-1) Li2S (1609 mAh g(-1) S) with a negligible charged potential barrier in the first cycle. The discharge capacity retained 791 mAh g(-1) Li2S (1137 mAh g(-1) S) after 100 cycles at 0.1C and exceeded 560 mAh g(-1) Li2S (805 mAh g(-1) S) at a high rate of 2C. Moreover, coupling the composite with Si thin film anode, a Li2S/Si full cell was produced, delivering a high specific capacity of ~900 mAh g(-1) Li2S (1294 mAh g(-1) S). The outstanding electrode performance of in-situ TG-Li2S composite was attributed to the well dispersed small Li2S nanoparticles and highly conductive graphene nanosheets, which provided merits of facile ionic and electronic transport, efficient utilization of the active material, and flexible accommodation of volume change.
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MicroRNA-451 induces epithelial-mesenchymal transition in docetaxel-resistant lung adenocarcinoma cells by targeting proto-oncogene c-Myc.
Eur. J. Cancer
PUBLISHED: 05-09-2014
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Epithelial-mesenchymal transition (EMT) has been reported to play a significant role in tumour metastasis as well as chemoresistance. However, the molecular mechanisms involved in chemotherapy-induced EMT are still unclear. MicroRNA (miRNA) expression and functions have been reported to contribute to phenotypic features of tumour cells. To investigate the roles of miRNAs in chemotherapy-induced EMT, we established two docetaxel-resistant lung adenocarcinoma (LAD) cell models (SPC-A1/DTX and H1299/DTX), which display EMT-like properties and gain increased invasion or migration activity. MiR-451 was found to be significantly downregulated in docetaxel-resistant LAD cells, and re-expression of miR-451 could reverse EMT to mesenchymal-epithelial transition (MET) and inhibit invasion and metastasis of docetaxel-resistant LAD cells both in vitro and in vivo. The proto-oncogene c-Myc was identified as a direct and functional target of miR-451, and further researches confirmed that overexpression of c-Myc which induced extracellular-signal-regulated kinase (ERK)-dependent glycogen synthase kinase-3 beta (GSK-3?) inactivation and subsequent snail activation is essential for acquisition of EMT phenotype induced by loss of miR-451. Furthermore, c-Myc was significantly upregulated in docetaxel-non-responding LAD tissues in comparison with docetaxel-responding tissues, and its expression was inversely correlated with miR-451 expression. This study first reported the involvement of miR-451/c-Myc/ERK/GSK-3? signalling axis in the acquisition of EMT phenotype in docetaxel-resistant LAD cells, suggesting that re-expression of miR-451 or targeting c-Myc will be a potential strategy for the treatment of chemoresistant LAD patients.
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Anti-inflammatory effect of sodium butyrate preconditioning during myocardial ischemia/reperfusion.
Exp Ther Med
PUBLISHED: 05-07-2014
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High mobility group box 1 protein (HMGB1) has an important role in myocardial ischemia/reperfusion (I/R) injury. Sodium butyrate, an inhibitor of histone deacetylase, has been shown to inhibit HMGB1 expression. In the present study, the effect of sodium butyrate on myocardial I/R injury in rats was investigated. Anesthetized male rats were intraperitoneally administered sodium butyrate (100 or 300 mg/kg) 30 min prior to the induction of ischemia. The rats were then subjected to ischemia for 30 min followed by reperfusion for 4 h. Infarct size, lactate dehydrogenase (LDH), creatine kinase (CK) and superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels were then measured. The expression of HMGB1 was assessed using western blot analysis. The results demonstrated that pretreatment with sodium butyrate (300 mg/kg) significantly reduced the infarct size, as well as the levels of LDH and CK (P<0.05). In addition, sodium butyrate (300 mg/kg) was shown to significantly inhibit the I/R-induced increase in the level of MDA and reduction in the level of SOD (P<0.05). Furthermore, treatment with sodium butyrate (300 mg/kg) was found to significantly inhibit the expression of TNF-?, IL-6 and HMGB1 induced by I/R injury (P<0.05). In conclusion, the results from the present study suggest that preconditioning with sodium butyrate may attenuate myocardial I/R injury by inhibition of the expression of inflammatory mediators during myocardial I/R.
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Plumbagin suppresses dendritic cell functions and alleviates experimental autoimmune encephalomyelitis.
J. Neuroimmunol.
PUBLISHED: 05-05-2014
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Plumbagin (PL, 5-hydroxy-2-methyl-1,4-naphthoquinone) is a herbal compound derived from medicinal plants of the Droseraceae, Plumbaginaceae, Dioncophyllaceae, and Ancistrocladaceae families. Reports have shown that PL exerts immunomodulatory activity and may be a novel drug candidate for immune-related disease therapy. However, its effects on dendritic cells (DCs), the most potent antigen-presenting cells (APCs), remain unclear. In this study, we demonstrate that PL inhibits the differentiation, maturation, and function of human monocyte-derived DCs. PL can also restrict the expression of Th1- and Th17-polarizing cytokines in mDC. In addition, PL suppresses DCs both in vitro and in vivo, as demonstrated by its effects on the mouse DC line DC2.4 and mice with experimental autoimmune encephalomyelitis (EAE), respectively. Notably, PL ameliorated the clinical symptoms of EAE, including central nervous system (CNS) inflammation and demyelination. Our results demonstrate the immune suppressive and anti-inflammatory properties of PL via its effects on DCs and suggest that PL could be a potential treatment for DC-related autoimmune and inflammatory diseases.
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A Chemoenzymatic Approach to Protein Immobilization onto Crystalline Cellulose Nanoscaffolds.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 04-23-2014
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The immobilization of bioactive molecules onto nanocellulose leads to constructs that combine the properties of the grafted compounds with the biocompatibility and low cytotoxicity of cellulose carriers and the advantages given by their nanometer dimensions. However, the methods commonly used for protein grafting suffer from lack of selectivity, long reaction times, nonphysiological pH ranges and solvents, and the necessity to develop a tailor-made reaction strategy for each individual case. To overcome these restrictions, a generic two-step procedure was developed that takes advantage of the highly efficient oxime ligation combined with enzyme-mediated protein coupling onto the surface of peptide-modified crystalline nanocellulose. The described method is based on efficient and orthogonal transformations, requires no organic solvents, and takes place under physiological conditions. Being site-directed and regiospecific, it could be applied to a vast number of functional proteins.
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Transoral approach for revision surgery of os odontoideum with atlantoaxial dislocation.
Orthopedics
PUBLISHED: 03-04-2014
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Revision surgery for os odontoideum with irreducible atlantoaxial dislocation with a transoral approach is not commonly seen. Typically, management of this type of atlantoaxial dislocation is through posterior fixation and fusion or transoral decompression and posterior fusion. This report describes revision surgery in a patient with os odontoideum who was treated with a transoral approach. A 50-year-old man was diagnosed with os odontoideum and atlantoaxial dislocation in 2007 and was treated surgically with posterior occipitocervical internal fixation and fusion. In 2012, he had recurrence of neck pain and numbness of the limbs. Neurologic function was grade D according to the standard neurologic classification of spinal cord injury from the American Spinal Injury Association. Because this was a revision surgery, the internal fixation implant was removed through a posterior approach and a transoral approach was used for release, reduction, internal fixation, and fusion. Two 6-mm cages filled with autogenous bone were introduced into the lateral mass spaces for bony fusion and distraction, and 2 cervical compressive mini-frames were used for fixation. Complete atlantoaxial reduction and decompression of the spinal cord were achieved. The patient reported improvement of symptoms after surgery. Movement of the extremities increased from grade III force to grade V, and neurologic status improved from American Spinal Injury Association grade D to grade E. A transoral approach for release, reduction, bony fusion, and fixation could be an effective procedure for the treatment of os odontoideum with irreducible atlantoaxial dislocation. It provides a new option for bony fusion and internal fixation of the atlantoaxial joint.
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Comparison of Percutaneous Transhepatic Variceal Embolization (PTVE) Followed by Partial Splenic Embolization versus PTVE Alone for the Treatment of Acute Esophagogastric Variceal Massive Hemorrhage.
J Vasc Interv Radiol
PUBLISHED: 03-01-2014
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To compare the efficacy of percutaneous transhepatic variceal embolization (PTVE) followed by partial splenic embolization (PSE) with that of PTVE alone for the treatment of acute massive hemorrhage of esophagogastric varices in patients with cirrhosis unable to undergo alternative procedures.
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Increasing available NADH supply during succinic acid production by Corynebacterium glutamicum.
Biotechnol. Prog.
PUBLISHED: 02-11-2014
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A critical factor in the biotechnological production of succinic acid with Corynebacterium glutamicum is the sufficient supply of NADH. It is conceivable that cofactor availability and the proportion of cofactor in the active form may play an important role in dictating the succinic acid yield. PntAB genes from Escherichia coli can directly catalyze the reversible hydride transfer and adjust the dynamic balance between NADP(H) and NAD(H). Hence, we studied the physiological effect of coenzyme systems by expressing the membrane-bound transhydrogenase pntAB genes. We have shown experimentally that the pntAB genes could function as an alternative source of NADH. In an anaerobic fermentation with C. glutamicum NC-3-pntAB, a 16% higher succinic acid yield and a 57% higher production from glucose were obtained by pntAB expression. Moreover, the formation of by-products was significantly decreased. The concomitant increase in the consumption of intracellular NADPH from 0.6 to 1.2 mmol/g CDW and the increased NADH/NAD(+) ratio resulted from introduction of pntAB, suggesting that the membrane-bound transhydrogenase converted excess NADPH to NADH for succinic acid production. Finally, we explored whether the transhydrogenase had different effects on the succinic acid formation on different carbon sources. The succinic acid yield was increased in the presence of pntAB by 16% on glucose, 7% on sucrose, and without large influence on fructose and xylose. The results of this study demonstrated that the effectiveness of cofactor manipulation could be a promising strategy applied in metabolic engineering. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 2014.
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Study on multilayer structures prepared from heparin and semi-synthetic cellulose sulfates as polyanions and their influence on cellular response.
Colloids Surf B Biointerfaces
PUBLISHED: 01-28-2014
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Multilayer coatings of polycationic chitosan paired with polyanionic semi-synthetic cellulose sulfates or heparin were prepared by the layer-by-layer method. Two different cellulose sulfates (CS) with high (CS2.6) and intermediate (CS1.6) sulfation degree were prepared by sulfation of cellulose. Multilayers were fabricated at pH 4 and the resulting films were characterized by several methods. The multilayer 'optical' mass, measured by surface plasmon resonance, showed little differences in the total mass adsorbed irrespective of which polyanion was used. In contrast, 'acoustic' mass, calculated from quartz crystal micro balance with dissipation monitoring, showed the lowest mass and dissipation values for CS2.6 (highest sulfation degree) multilayers indicating formation of stiffer layers compared to heparin and CS1.6 layers which led to higher mass and dissipation values. Water contact angle and zeta potential measurements indicated formation of more distinct layers with using heparin as polyanion, while use of CS1.6 and CS2.6 resulted into more fuzzy intermingled multilayers. CS1.6 multilayers significantly supported adhesion and growth of C2C12 cells where as only few cells attached and started to spread initially on CS2.6 layers but favoured long term cell growth. Contrastingly cells adhered and grew poorly on to the layers of heparin. This present study shows that cellulose sulfates are attractive candidates for multilayer formation as potential substratum for controlled cell adhesion. Since a peculiar interaction of cellulose sulfates with growth factors was found during previous studies, immobilization of cellulose sulfate in multilayer systems might be of great interest for tissue engineering applications.
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Significant association between DRD3 gene body methylation and schizophrenia.
Psychiatry Res
PUBLISHED: 01-13-2014
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The current study was the first one to reveal the contribution of DRD3 methylation to the risk of different SCZ subtypes. This study was involved with a total of 30 paranoid (15 males and 15 females) and 29 undifferentiated (15 males and 14 females) SCZ patients and 26 age- and gender-matched controls. Our results showed a significant association of CpG2 with SCZ. A breakdown analysis by gender showed that CpG2 and CpG3 methylation were significantly higher in male patients than male controls, and that CpG5 methylation was significantly higher in female patients than female controls. A further breakdown analysis by both gender and SCZ subtype showed that CpG2 and CpG3 methylation were significantly higher in male paranoid SCZ and male undifferentiated SCZ than male controls. In contrast, CpG2 and CpG3 methylation were significantly lower in female undifferentiated SCZ than female controls. Additionally, CpG5 methylation was significantly higher in female paranoid SCZ than female controls. In conclusion, our findings supported that DRD3 gene body hypermethylation was significantly associated with the risk of SCZ. Future study is needed to clarify the mechanisms by which DRD3 gene body hypermethylation contributes to the risk of SCZ.
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Elevation of extracellular Ca2+ induces store-operated calcium entry via calcium-sensing receptors: a pathway contributes to the proliferation of osteoblasts.
PLoS ONE
PUBLISHED: 01-01-2014
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The local concentration of extracellular Ca(2+) ([Ca(2+)]o) in bone microenvironment is accumulated during bone remodeling. In the present study we investigated whether elevating [Ca(2+)]o induced store-operated calcium entry (SOCE) in primary rat calvarial osteoblasts and further examined the contribution of elevating [Ca(2+)]o to osteoblastic proliferation.
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Replication of the 4p16 susceptibility locus in congenital heart disease in Han Chinese populations.
PLoS ONE
PUBLISHED: 01-01-2014
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Congenital heart disease (CHD) is the most common form of congenital human birth anomalies and a leading cause of perinatal and infant mortality. Some studies including our published genome-wide association study (GWAS) of CHD have indicated that genetic variants may contribute to the risk of CHD. Recently, Cordell et al. published a GWAS of multiple CHD phenotypes in European Caucasians and identified 3 susceptibility loci (rs870142, rs16835979 and rs6824295) for ostium secundum atrial septal defect (ASD) at chromosome 4p16. However, whether these loci at 4p16 confer the predisposition to CHD in Chinese population is unclear. In the current study, we first analyzed the associations between these 3 single nucleotide polymorphisms (SNPs) at 4p16 and CHD risk by using our existing genome-wide scan data and found all of the 3 SNPs showed significant associations with ASD in the same direction as that observed in Cordell's study, but not with other subtypes- ventricular septal defect (VSD) and ASD combined VSD. As these 3 SNPs were in high linkage disequilibrium (LD) in Chinese population, we selected one SNP with the lowest P value in our GWAS scan (rs16835979) to perform a replication study with additional 1,709 CHD cases with multiple phenotypes and 1,962 controls. The significant association was also observed only within the ASD subgroup, which was heterogeneous from other disease groups. In combined GWAS and replication samples, the minor allele of rs16835979 remained significant association with the risk of ASD (OR = 1.22, 95% CI = 1.08-1.38, P = 0.001). Our findings suggest that susceptibility loci of ASD identified from Cordell's European GWAS are generalizable to Chinese population, and such investigation may provide new insights into the roles of genetic variants in the etiology of different CHD phenotypes.
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Protein signature for non-small cell lung cancer prognosis.
Am J Cancer Res
PUBLISHED: 01-01-2014
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Current histopathological classification and TNM staging have limited accuracy in predicting survival and stratifying patients for appropriate treatment. The goal of the study is to determine whether the expression pattern of functionally important regulatory proteins can add additional values for more accurate classification and prognostication of non-small lung cancer (NSCLC).
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Characteristics of urinary tract infection pathogens and their in vitro susceptibility to antimicrobial agents in China: data from a multicenter study.
BMJ Open
PUBLISHED: 12-17-2013
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This study assessed the characteristics of pathogens identified in clinical isolates from patients with urinary tract infection (UTI) and their in vitro sensitivity to commonly used antibiotics in the clinical setting in China.
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Macrocycle contraction and expansion of a dihydrosapphyrin isomer.
J. Am. Chem. Soc.
PUBLISHED: 12-13-2013
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Cyclization of a pentapyrrane with two terminal ?-linked pyrroles afforded a dihydrosapphyrin isomer (1) with the pyrroles linked in a unique ?,?-?,? mode, which was rather reactive, and thus it readily underwent a ring-contracted rearrangement to a pyrrolyl norrole (2), and succeeding ring expansion to a terpyrrole-containing isosmaragdyrin analogue (4). 1, 2, and 4 contain the internal ring pathways with a minimum of 17, 15, and 16 atoms, respectively. 1, 2, and 4 are almost nonfluorescent, whereas the complex of 2 with Zn(2+) shows a distinct NIR emission peak at 741 nm. The unprecedented pyrrole transformation chemistry by confusion approach is illustrated.
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Evaluation of three-dose fosfomycin tromethamine in the treatment of patients with urinary tract infections: an uncontrolled, open-label, multicentre study.
BMJ Open
PUBLISHED: 12-07-2013
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To evaluate the clinical and microbiological efficacy and safety of three doses of 3 g fosfomycin tromethamine administered orally to treat lower urinary tract infections.
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[Analyses of risk factors for deep vein thrombosis in lower extremities].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-05-2013
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To explore the risk factors of deep vein thrombosis (DVT) in lower extremities.
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Increased serum HMGB1 is related to oxidative stress in patients with atrial fibrillation.
J. Int. Med. Res.
PUBLISHED: 11-23-2013
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To investigate the relationship between the serum concentration of high mobility group box 1 protein (HMGB1) and oxidative stress in patients with atrial fibrillation (AF).
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Hypertrophy and Fibrosis of the Ligamentum Flavum in Lumbar Spinal Stenosis is Associated with Increased Expression of LPA and LPAR1.
J Spinal Disord Tech
PUBLISHED: 11-20-2013
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Histological, immunohistochemical, and ELISA analysis of the human ligamentum flavum (LF).
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Assessment of 64-row computed tomographic angiography for diagnosis and pretreatment planning in pulmonary sequestration.
Radiol Med
PUBLISHED: 11-15-2013
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This study was done to evaluate the clinical implications and results of a prospective protocol using 64-row computed tomographic angiography (CTA) for diagnosis and pre-treatment planning in pulmonary sequestration (PS).
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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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