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Find video protocols related to scientific articles indexed in Pubmed.
Caffeic acid inhibits the uptake of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) by inducing the efflux transporters expression in Caco-2 cells.
Biol. Pharm. Bull.
PUBLISHED: 11-18-2014
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2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is formed as a by-product of the Maillard reaction during cooking and frying of protein-rich foods at high temperatures. PhIP is metabolized in the liver by cytochrome P450 1A1/2 to carcinogenic metabolite N-hydroxy PhIP, which can form DNA adduct. The ABC transporters, P-glycoprotein (P-gp), multidrug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP) are capable of transporting the food-borne procarcinogen PhIP back to the intestinal lumen. In the present study, the uptake and efflux of PhIP were assessed by determining apparent bidirectional permeability coefficients and efflux ratio. The efflux ratio of PhIP with 10 ?M caffeic acid was significantly increased compared with control. The mRNA levels of efflux transporters were measured to evaluate the effect of caffeic acid in the presence of PhIP on efflux-mediated transport of PhIP. Caco-2 cells exposed to 10 ?M caffeic acid for 3 and 6 h also exhibited higher mRNA levels of P-gp and BCRP than those of control. In contrast, the mRNA level of MRP2 was only slightly induced after 3 h and 6 h. Therefore, caffeic acid at low concentration is expected to be used not only as an antioxidant, but also as an inhibitor of the absorption of food borne carcinogen heterocyclic amines. However, further studies, especially in vivo studies, are required to confirm these results.
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Association of selenoprotein S gene polymorphism with ischemic stroke in a Chinese case-control study.
Blood Coagul. Fibrinolysis
PUBLISHED: 11-13-2014
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Previous studies showed that selenoprotein S (SELS) was associated with a range of inflammatory markers, and its gene expression was influenced by a polymorphism in the promoter region. The genetic basis of the ischemic stroke has now been largely determined, so the aim of the study was to examine the role of SELS genetic variants in the ischemic stroke risk in a Chinese population. We conducted a case-control study with 239 ischemic stroke patients and 240 controls. Two single-nucleotide polymorphisms (SNPs) in SELS genes were analyzed for association with the risk of ischemic stroke in the Chinese Han population. No evidence of ischemic stroke association was observed with the SNP rs34713741. Interestingly, the strongest evidence showed that SELS SNP rs4965814 was associated with ischemic stroke (P?
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Structures and energies of Cu clusters on Fe and Fe3C surfaces from density functional theory computation.
Phys Chem Chem Phys
PUBLISHED: 11-07-2014
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Spin-polarized density functional theory computations have been carried out to study the stable adsorption configurations of Cun (n = 1-7, 13) on Fe and Fe3C surfaces for understanding the initial stages of copper promotion in catalysis. At low coverage, two-dimensional aggregation is more preferred over dispersion and three-dimensional aggregation on the Fe(110) and Fe(100) surfaces as well as the metallic Fe3C(010) surfaces, while dispersion is more favorable over aggregation on the Fe(111) surface. On the Fe3C(001) and Fe3C(100) surfaces with exposed iron and carbon atoms, the adsorbed Cu atoms prefer dispersion at low coverage, while aggregation along the iron regions at high coverage. On the iron surfaces, the adsorption energies of Cun (n = 2-7) are highest on Fe(111), medium on Fe(100) and lowest on Fe(110). On the Fe3C surfaces, the adsorption energies of Cun (n = 1-3) are highest on Fe3C(100), medium on Fe3C(010) and lowest on Fe3C(001), while, for n = 4-7 and 13, Fe3C(010) has stronger adsorption than Fe3C(100). On the basis of their differences in electronegativity, the adsorbed Cu atoms can oxidize the metallic Fe(110), Fe(100) and Fe3C(010) surfaces and become negatively charged. On the Fe3C(001) and Fe3C(100) surfaces with exposed iron and carbon atoms, the adsorbed Cu atoms interacting with surface carbon atoms are oxidized and positively charged. Unlike the most stable Fe(110) and Fe3C(001) surfaces, where the Fe(110) surface has stronger Cu affinity than the Fe3C(001) surface, which is in agreement with the experimental finding, the less and least stable Fe3C(010) and Fe3C(100) surfaces have stronger Cu affinities than the Fe(110) and Fe(100) surfaces. Since less stable facets are not preferably formed thermodynamically, it is crucial to prepare such surfaces to explore Cu adsorption and promotion, and this provides challenges to surface sciences.
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[STC-1 is involved in anti-hypoxia proliferative balance of renal cancer cells by down-regulation of intracellular Ca2+ and HIF-1? levels].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 11-06-2014
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To investigate effects of stanniocalcin-1?STC-1? on proliferation balance under hypoxic condition in renal cancer cells and its mechanism. METHODS? Hypoxic model was induced on renal cancer GRC-1 cells?Group H?? the cells were treated with STC-1 protein at concentrations of 0.1 nmol/L ?H1?? 0.5 nmol/L ?H2?? 1.0 nmol/L ?H3?? or normal saline ?H0? for 48 h? respectively. Cells proliferation was measured by MTT assay; mRNA and protein expressions of hypoxia inducible factor 1??HIF-1?? and STC-1 in GRC-1 cells were detected by RT-PCR and ELISA?respectively; the intracellular levels of Ca2+ and adenosine triphosphate?ATP? were determined by fluorescence spectrophotometry and spectrophotometry?respectively. RESULTS?The expression of HIF-1??STC-1 and Ca2+ levels were increased in GRC-1 cells under hypoxia condition; STC-1 reversed these changes in a dose-effect manner. Hypoxia significantly inhibited cell proliferation and the generation of ATP in GRC-1 cells and exogenous STC-1 reversed the effects of hypoxia; ATP generation increased gradually with increasing STC-1 concentration?but the cell proliferation was reduced. CONCLUSION?Exogenous STC-1 can promote the proliferation of renal cancer cells in hypoxia condition by reducing HIF-1? expression and Ca2+ content and increased ATP production?but the progressive inhibition of HIF-1 ? hindered the renal carcinoma cell proliferation further?which indicates that STC-1 may be involved in anti-hypoxia proliferative balance of renal cancer cells.
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Reduced Expression of Growth and Differentiation Factor-9 (GDF9) Is Associated with Aggressive Behaviour of Human Clear-cell Renal Cell Carcinoma and Poor Patient Survival.
Anticancer Res.
PUBLISHED: 11-05-2014
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Growth and differentiation factor-9 (GDF9) is a member of the bone morphogentic protein (BMP) family. GDF9 was recently shown to be a regulator of the development and spread of cancer cells, including kidney cancer cells. However, the clinical implication of GDF9 in human clear-cell renal cell carcinoma (CCRCC) remains unknown. In the present study, the expression of GDF9 in human CCRCC tissues, and correlation between GDF9 and pathological grade and stage of the tumours were examined in CRCC specimens.
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Peritumoral Neuropilin-1 and VEGF receptor-2 expression increases time to recurrence in hepatocellular carcinoma patients undergoing curative hepatectomy.
Oncotarget
PUBLISHED: 10-22-2014
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Purpose: To determined Neuropilin-1 (NRP-1) and vascular endothelial growth factor receptor 2 (VEGFR-2) expression in the tumoral and peritumoral tissues of 214 treatment-naïve HCC patients and its correlation with overall survival (OS) and time to recurrence (TTR). Experimental Design: NRP-1 and VEGFR-2 expression were examined by tissue microarray and peritumoral hypoxia by pimonidazole staining and angiogenesis by microvessel density (MVD). OS and TTR were evaluated by Kaplan-Meier analysis and log-rank test. Results: Peritumoral NRP-1 and VEGFR-2 expression were significantly higher than that of the tumoral tissue (p < 0.001 for both), and high peritumoral expression of both factors was negatively associated with tumor size (p < 0.001 for both). Patients with high peritumoral expression of both proteins had the longest median OS (>94.0 months) and TTR (>84.0 months). The multivariate Cox proportional hazards analysis revealed that patients with high peritumoral expression of both NRP-1 and VEGFR-2 were more than 4 times less likely to have recurrence (p = 0.004) and more than 10 times likely to survive (p < 0.001). Conclusions: Peritumoral NRP-1 and VEGFR-2 expression is associated with prolonged TTR and extended OS of HCC patients and both may be useful as predictors of surgical outcome of HCC patients and explored as potential therapeutic targets.
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A study on the mechanical characteristics of the EBM-printed Ti-6Al-4V LCP plates in vitro.
J Orthop Surg Res
PUBLISHED: 10-08-2014
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The electron beam melting (EBM) Ti-6Al-4V material technology has been developed over a short time period. It was introduced through a research to develop Ti-6Al-4V implants for patients, but EBM printed locking compression plates have not been used for clinical implants. The main purpose of this study is to find whether the EBM Ti-6Al-4V plate suit for clinical implants.
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Highly efficient molecular nickel catalysts for electrochemical hydrogen production from neutral water.
Chem. Commun. (Camb.)
PUBLISHED: 10-04-2014
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A series of nickel complexes containing N5-pentadentate ligands with different amine-to-pyridine ratios were studied for electrochemical H2 production in neutral water and the one with a diamine-tripyridine ligand displays a TON of up to 308?000 over 60 h electrolysis at -1.25 V vs. SHE, with a Faradaic efficiency of ?91%.
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Novel Urethral Sheath to Manage Bladder Calculi.
J. Endourol.
PUBLISHED: 10-01-2014
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Abstract Purpose: To explore the role of a new urethral sheath in transurethral lithotripsy for bladder calculi. Methods: The 120 cases with bladder stone (BS) models were divided into three groups. One stone was placed in the bladder for each case. A total of 40 cases were included in each group. Then, the 40 cases were further divided into control group 1, control group 2, and the test group with 15, 15, and 10 cases, respectively. The sizes of the stones used for each group were 1.5, 2.0, and 3.0?cm, respectively. In control group 1, the ureteroscope was used. In control group 2, the ureteroscope was inserted via the outer sheath of the resectoscope. In the test group, the new sheath was used. Results: Mean BS removal times in control group 1, control group 2, and the test group were 86±15.5, 45.5±12.2, and 11.5±5.5 minutes, respectively (P=0.001, n=40). For a BS with a diameter of 1.5?cm, the mean removal times were 27.5±4.8, 13.5±3.6, and 5.5±2 minutes, respectively (P=0.00). For a BS with a diameter of 2.0?cm, the mean removal times were 79.5±8.8, 41.5±4.5, and 12.5±3.5 minutes, respectively (P=0.00). For a BS with a diameter of 3.0?cm, the mean removal times were 189.5±28, 141.5±23.2, and 56.5±13 minutes, respectively (P=0.001). Conclusion: The new JQL sheath is suitable for the transurethral management of BS and can significantly improve the efficiency, thus resulting in a simple and effective operation.
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Lack of association between LEPR Q223R polymorphisms and cancer susceptibility: evidence from a meta-analysis.
J BUON
PUBLISHED: 09-28-2014
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The results from the published studies on the association between LEPR genetic polymorphisms and cancer risk are conflicting. The common LEPR Q223R genetic polymorphism has been reported to be functional and may contribute to genetic susceptibility to cancer. However, the association between LEPR Q223R genetic polymorphism and cancer risk remains inconclusive.
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Association of LEPR K109R polymorphisms with cancer risk: a systematic review and pooled analysis.
J BUON
PUBLISHED: 09-28-2014
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This meta-analysis was conducted to evaluate the association between LEPR K109R (rs1137100) genetic polymorphism and cancer risk.
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[Prevention against and treatment of doxorubicin-induced acute cardiotoxicity by dexrazoxane and schisandrin B].
Yao Xue Xue Bao
PUBLISHED: 09-20-2014
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In this study, it is to compare the effectiveness of prevention against and treatment of doxorubicin (DOX) induced cardiotoxicity by dexrazoxane and schisandrin B (Sch B) in rats. Sprague-Dawley (SD) rats were randomly divided into the following 6 groups: normal saline group, DOX group, DOX+DEX group, DOX+Sch B (80 mg x kg(-1)) group, DOX+Sch B (40 mg x kg(-1)) group and DOX+Sch B (20 mg x kg(-1)) group. The results showed that Sch B could combat the increase of myocardial enzymes in peripheral blood, decrease of the enzyme activity of myocardial tissue antioxidant enzymes and disorders of systolic and diastolic function of heart in rats intravenously injected with doxorubicin (15 mg x kg(-1)). Sch B was better than DEX in protecting rat against DOX-induced the symptoms. Sch B could protect rat against DOX-induced acute cardiomyopathy and has clinical potential applications.
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[Risk factors associated with incisional surgical site infection in colorectal cancer surgery with primary anastomosis].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 09-16-2014
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To investigate the incidence of surgical site infection (SSI) and risk factors in colorectal cancer surgery patients.
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[Dynamic observation of EB virus DNA load before and after the treatment in patients with nasopharyngeal carcinoma and its clinical significance].
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi
PUBLISHED: 09-16-2014
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Dynamic observation of Epstein-Barr virus (EBV) DNA load before and after the treatment in patients with Nasopharyngeal carcinoma (NPC), predicting the incidence of distant metastasis and offering more personalised choice of therapies.
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Identification of an antitumor immune response of polyhistidine through a toll-like receptor 4-dependent manner.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-12-2014
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Polyhistidine is widely used for the delivery of nucleic acids and antibodies into the cell cytoplasm. However, little attention has been concerned on the effect of polyhistidine on the immune system. In this work, we identify a novel function of polyhistidine as an activator of the immune system. Single-molecule fluorescence imaging and single-molecule force measurements show that polyhistidine binds specifically to the toll-like receptor 4 (TLR4), inducing receptor dimerization and activation. Moreover, in a B16 melanoma model we demonstrate that polyhistidine treatment inhibits tumor growth in TLR4(+/+) but not TLR4(-/-) mice. These results suggest the potential use of polyhistidine for cancer immunotherapy.
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Compound heterozygous PLEC mutations in a patient of consanguineous parentage with epidermolysis bullosa simplex with muscular dystrophy and diffuse alopecia.
Int. J. Dermatol.
PUBLISHED: 09-12-2014
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Epidermolysis bullosa simplex with muscular dystrophy (EBS-MD; OMIM 226670) is an autosomal recessive form of EBS, characterized by skin blistering at birth and delayed onset of muscle dystrophy. Mutations in PLEC, the gene encoding plectin, have been identified to be causal for EBS-MD. We report a case of EBS-MD with diffuse alopecia. Genetic study revealed the patient carrying compound heterozygous mutations in PLEC despite the consanguineous parentage.
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[Preparation and up-conversion luminescence properties of Yb3+/Tm3+ co-doped Sb2O4 powder].
Guang Pu Xue Yu Guang Pu Fen Xi
PUBLISHED: 09-12-2014
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The Sb2O4:Yb3+, Tm3+ up-conversion luminescence powder with excellent physical, chemical stability and relative low phonon energy was synthesized by the high temperature solid-state reaction and its up-conversion luminescence property was investigated. Under the 980 nm excitation, infrared and blue up-conversion emissions centered at 800 and 480 nm were observed, which were assigned to the 1G4-->3H6 and 3H4-->3 He transitions of Tm2+, respectively. The influence of Yb3+ and Tm3+ concentration on the up-conversion emission property was also obtained. The up-conversion luminescence increases with increasing of Yb3+ and Tm3+ concentration. Additionally, the up-conversion luminescence mechanism was discussed based on the dependence of Tm3+ up-conversion luminescence on pump power. It is interesting that two photon excitation processes for blue and infrared emission were observed in the Sb2O04: Yb3+, Tm3+ powder under a 980 nm excitation. Based on the energy level diagram of Tma3 and Yb2+ ions, we think that two photons blue emission is contributed to the cooperation energy transfer between Tm"+ and Yb3+ ions. We believe that the Sbz04 : Yb3 , Tm2+ up-conversion luminescence powder will have potential application for new optical devices in up-conversion color displays, sensors, detection of infrared radiation, and lasers.
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Quercetin suppresses insulin receptor signaling through inhibition of the insulin ligand-receptor binding and therefore impairs cancer cell proliferation.
Biochem. Biophys. Res. Commun.
PUBLISHED: 09-04-2014
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Although the flavonoid quercetin is known to inhibit activation of insulin receptor signaling, the inhibitory mechanism is largely unknown. In this study, we demonstrate that quercetin suppresses insulin induced dimerization of the insulin receptor (IR) through interfering with ligand-receptor interactions, which reduces the phosphorylation of IR and Akt. This inhibitory effect further inhibits insulin stimulated glucose uptake due to decreased cell membrane translocation of glucose transporter 4 (GLUT4), resulting in impaired cancer cell proliferation. The effect of quercetin in inhibiting tumor growth was also evident in an in vivo model, indicating a potential future application for quercetin in the treatment of cancers.
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Convergent functional architecture of the superior parietal lobule unraveled with multimodal neuroimaging approaches.
Hum Brain Mapp
PUBLISHED: 09-02-2014
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The superior parietal lobule (SPL) plays a pivotal role in many cognitive, perceptive, and motor-related processes. This implies that a mosaic of distinct functional and structural subregions may exist in this area. Recent studies have demonstrated that the ongoing spontaneous fluctuations in the brain at rest are highly structured and, like coactivation patterns, reflect the integration of cortical locations into long-distance networks. This suggests that the internal differentiation of a complex brain region may be revealed by interaction patterns that are reflected in different neuroimaging modalities. On the basis of this perspective, we aimed to identify a convergent functional organization of the SPL using multimodal neuroimaging approaches. The SPL was first parcellated based on its structural connections as well as on its resting-state connectivity and coactivation patterns. Then, post hoc functional characterizations and connectivity analyses were performed for each subregion. The three types of connectivity-based parcellations consistently identified five subregions in the SPL of each hemisphere. The two anterior subregions were found to be primarily involved in action processes and in visually guided visuomotor functions, whereas the three posterior subregions were primarily associated with visual perception, spatial cognition, reasoning, working memory, and attention. This parcellation scheme for the SPL was further supported by revealing distinct connectivity patterns for each subregion in all the used modalities. These results thus indicate a convergent functional architecture of the SPL that can be revealed based on different types of connectivity and is reflected by different functions and interactions. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.
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[GC-MS analysis for volatile components from alpiniae katsumadai semen by three extraction methods].
Zhong Yao Cai
PUBLISHED: 09-02-2014
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To analysis the volatile components in Alpiniae Katsumadai Semen.
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Nickel complex with internal bases as efficient molecular catalyst for photochemical H2 production.
ChemSusChem
PUBLISHED: 09-01-2014
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A Ni complex with internal bases that contain bipyridine-derived ligands, [Ni(L)2 (H2 O)2 ](BF4 )2 ([1](BF4 )2 , L=2-(2-pyridyl)-1,8-naphthyridine), and a reference complex that bears analogous bipyridine-derived ligands but without an internal base, [Ni(L')3 ](BF4 )2 ([2](BF4 )2 , L'=2-(2-pyridyl)quinoline), were synthesized and characterized. The electrochemical properties of these complexes were studied in CH3 CN, H2 O, and a mixture of EtOH/H2 O. The fluorescence spectroscopic studies suggest that both dynamic and the sphere-of-action static quenching exist in the fluorescein Fl(2-) /[1](2+) and Fl(2-) /[2](2+) systems. These noble-metal-free molecular systems were studied for photocatalytic H2 generation. Under optimal conditions, the turnover number of H2 evolution reaches 3230 based on [1](2+) , whereas [2](2+) displays only approximately one third of the turnover of [1](2+) . A plausible mechanism for the catalytic H2 generation by [1](2+) is presented based on DFT calculations.
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Exome sequencing reveals mutation in GJA1 as a cause of keratoderma-hypotrichosis-leukonychia totalis syndrome.
Hum. Mol. Genet.
PUBLISHED: 08-28-2014
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Keratoderma-hypotrichosis-leukonychia totalis syndrome (KHLS) is an extremely rare, autosomal-dominant disorder characterized by severe skin hyperkeratosis, congenital alopecia and leukonychia totalis. The genetic defect underlying KHLS remained undetermined. By performing whole-exome sequencing in a family with KHLS, we identified a heterozygous mutation (c.23G>T [p.Gly8Val]) in GJA1, which cosegregated with the phenotype in the family. In an additional affected individual, we also found the identical de novo mutation which was absent in his unaffected family members. GJA1 encodes a gap junction protein connexin 43 (Cx43) which is ubiquitously expressed in various organs, including the epidermis and hair follicles. In vitro studies on HEK293 cells expressing Cx43(Gly8Val) found that the protein formed gap junction plaques between adjacent transfected cells, as observed in the wild-type. Dye-transfer experiments by microinjection of Lucifer yellow displayed functional gap junction of the Cx43(Gly8Val) mutant. Using patch clamp and Ca(2+) imaging methods, we observed that the Cx43(Gly8Val) hemichannel had significantly more openings than Cx43(WT), facilitating Ca(2+) influx at resting potential. Such gain-of-function effect might result in cytoplasmic Ca(2+) overload, accelerated apoptosis of keratinocytes and subsequent skin hyperkeratosis. Taken together, our results demonstrated that, with probably enhanced hemichannel activities, a mutation in GJA1 is linked to KHLS without extracutaneous involvement.
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The concordance between RNA-seq and microarray data depends on chemical treatment and transcript abundance.
Nat. Biotechnol.
PUBLISHED: 08-24-2014
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The concordance of RNA-sequencing (RNA-seq) with microarrays for genome-wide analysis of differential gene expression has not been rigorously assessed using a range of chemical treatment conditions. Here we use a comprehensive study design to generate Illumina RNA-seq and Affymetrix microarray data from the same liver samples of rats exposed in triplicate to varying degrees of perturbation by 27 chemicals representing multiple modes of action (MOAs). The cross-platform concordance in terms of differentially expressed genes (DEGs) or enriched pathways is linearly correlated with treatment effect size (R(2)?0.8). Furthermore, the concordance is also affected by transcript abundance and biological complexity of the MOA. RNA-seq outperforms microarray (93% versus 75%) in DEG verification as assessed by quantitative PCR, with the gain mainly due to its improved accuracy for low-abundance transcripts. Nonetheless, classifiers to predict MOAs perform similarly when developed using data from either platform. Therefore, the endpoint studied and its biological complexity, transcript abundance and the genomic application are important factors in transcriptomic research and for clinical and regulatory decision making.
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The effect of electromagnetic fields on the proliferation and the osteogenic or adipogenic differentiation of mesenchymal stem cells modulated by dexamethasone.
Bioelectromagnetics
PUBLISHED: 08-21-2014
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Although glucocorticoids provide benefits for inflammation or autoimmune disorders, high-dose and long-term use could cause osteonecrosis or osteoporosis as adverse effect for patients. Electromagnetic field (EMF) treatments have been clinically used for many years to promote fracture healing, but whether EMF can attenuate the deleterious effects of glucocorticoids is not clear. In this study, the effects of different concentrations of dexamethasone (DEX) on proliferation and adipogenic or osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) were detected and compared, and the effects of EMF treatment (15?Hz, 1?mT, 4?h/day) on 0.1?µM DEX-modulated BMSCs' proliferation and adipogenic or osteogenic differentiation were investigated. Higher concentrations of DEX (0.1 and 1?µM) inhibited proliferation of BMSCs but promoted expression of adipogenic-related genes, increasing the number of lipid droplets. In the early stage of differentiation, DEX restrained expression of RUNX2 and alkaline phosphatase (ALP), but amplified expression of ALP and osteopontin (OPN) in the late stage. EMF treatment of BMSCs influenced by 0.1?µM DEX inhibited the high expression of adipogenic-related genes, stimulated the expression of RUNX2, ALP, OPN, and osteocalcin, and increased the activity of ALP. EMF exposure augmented the expression of p-ERK, which DEX reduced. After using mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK signaling pathway inhibitor, U0126, the effect of EMF was reduced. In conclusion, EMF exposure accelerates BMSCs proliferation, inhibits adipogenic differentiation, and promotes osteogenic differentiation of BMSCs modulated by DEX, and these effects are mediated at least in part by MEK/ERK signaling pathway.
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Impact of multiple negative charges on blood clearance and biodistribution characteristics of 99mTc-labeled dimeric cyclic RGD peptides.
Bioconjug. Chem.
PUBLISHED: 08-21-2014
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This study sought to evaluate the impact of multiple negative charges on blood clearance kinetics and biodistribution properties of (99m)Tc-labeled RGD peptide dimers. Bioconjugates HYNIC-P6G-RGD2 and HYNIC-P6D-RGD2 were prepared by reacting P6G-RGD2 and P6D-RGD2, respectively, with excess HYNIC-OSu in the presence of diisopropylethylamine. Their IC50 values were determined to be 31 ± 5 and 41 ± 6 nM, respectively, against (125)I-echistatin bound to U87MG glioma cells in a whole-cell displacement assay. Complexes [(99m)Tc(HYNIC-P6G-RGD2)(tricine)(TPPTS)] ((99m)Tc-P6G-RGD2) and [(99m)Tc(HYNIC-P6D-RGD2)(tricine)(TPPTS)] ((99m)Tc-P6D-RGD2) were prepared in high radiochemical purity (RCP > 95%) and specific activity (37-110 GBq/?mol). They were evaluated in athymic nude mice bearing U87MG glioma xenografts for their biodistribution. The most significant difference between (99m)Tc-P6D-RGD2 and (99m)Tc-P6G-RGD2 was their blood radioactivity levels and tumor uptake. The initial blood radioactivity level for (99m)Tc-P6D-RGD2 (4.71 ± 1.00%ID/g) was ?5× higher than that of (99m)Tc-P6G-RGD2 (0.88 ± 0.05%ID/g), but this difference disappeared at 60 min p.i. (99m)Tc-P6D-RGD2 had much lower tumor uptake (2.20-3.11%ID/g) than (99m)Tc-P6G-RGD2 (7.82-9.27%ID/g) over a 2 h period. Since HYNIC-P6D-RGD2 and HYNIC-P6G-RGD2 shared a similar integrin ?v?3 binding affinity (41 ± 6 nM versus 31 ± 5 nM), the difference in their blood activity and tumor uptake is most likely related to the nine negative charges and high protein binding of (99m)Tc-P6D-RGD2. Despite its low uptake in U87MG tumors, the tumor uptake of (99m)Tc-P6D-RGD2 was integrin ?v?3-specific. SPECT/CT studies were performed using (99m)Tc-P6G-RGD2 in athymic nude mice bearing U87MG glioma and MDA-MB-231 breast cancer xenografts. The SPECT/CT data demonstrated the tumor-targeting capability of (99m)Tc-P6G-RGD2, and its tumor uptake depends on the integrin ?v?3 expression levels on tumor cells and neovasculature. It was concluded that the multiple negative charges have a significant impact on the blood clearance kinetics and tumor uptake of (99m)Tc-labeled dimeric cyclic RGD peptides.
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MiR-136 targets E2F1 to reverse cisplatin chemosensitivity in glioma cells.
J. Neurooncol.
PUBLISHED: 08-20-2014
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MicroRNAs (miRNAs) have gained much attention due to their critical roles in diverse biological events, including tumorigenesis. In this study, we demonstrate that miR-136 is down-regulated in two cohorts of patients with glioma. Furthermore, the low-level expression of miR-136 is significantly associated with a more aggressive and/or poor prognostic phenotype of patients with gliomas. Both gain- and loss-of-function experiments showed that miR-136 expression can reverse cisplatin resistance and enhance the response to cisplatin treatment. Furthermore, we identified a novel direct target of miR-136, the E2F transcription factor 1 (E2F1) oncogene. Depletion of E2F1 recapitulated the tumor-suppressive functions of miR-136, whereas re-expression of E2F1 attenuated the function of miR-136 in glioma cells. Finally, we revealed that miR-136 is inversely correlated with E2F1 expression in human glioma samples. The present study provides functional and mechanistic links between the tumor suppressor miR-136 and the oncogene E2F1 for the development of chemoresistance in human glioma. Our results indicate that targeting of the miR-136/E2F1 axis may provide a promising therapeutic approach to treat glioma.
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A Molecular Copper Catalyst for Electrochemical Water Reduction with a Large Hydrogen-Generation Rate Constant in Aqueous Solution.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 08-15-2014
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The copper complex [(bztpen)Cu](BF4 )2 (bztpen=N-benzyl-N,N',N'-tris(pyridin-2-ylmethyl)ethylenediamine) displays high catalytic activity for electrochemical proton reduction in acidic aqueous solutions, with a calculated hydrogen-generation rate constant (kobs ) of over 10000 s(-1) . A turnover frequency (TOF) of 7000 h(-1) ?cm(-2) and a Faradaic efficiency of 96?% were obtained from a controlled potential electrolysis (CPE) experiment with [(bztpen)Cu](2+) in pH 2.5 buffer solution at -0.90 V versus the standard hydrogen electrode (SHE) over two hours using a glassy carbon electrode. A mechanism involving two proton-coupled reduction steps was proposed for the dihydrogen generation reaction catalyzed by [(bztpen)Cu](2+) .
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Metformin restores intermediate-conductance calcium-activated K+ channel- and small-conductance calcium-activated K+ channel-mediated vasodilatation impaired by advanced glycation end products in rat mesenteric artery.
Mol. Pharmacol.
PUBLISHED: 08-14-2014
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The present study was designed to investigate the effect of metformin on the impairment of intermediate-conductance and small-conductance Ca(2+)-activated potassium channels (IKCa and SKCa)-mediated relaxation in diabetes and the underlying mechanism. The endothelial vasodilatation function of mesenteric arteries was assessed with the use of wire myography. Expression levels of IKCa and SKCa and phosphorylated Thr(172) of AMP-activated protein kinase (AMPK) were measured using Western blot technology. The channel activity was observed using a whole-cell patch voltage clamp. Reactive oxygen species (ROS) were measured using dihydroethidium and 2',7'-dichlorofluorescein diacetate. Metformin restored the impairment of IKCa- and SKCa-mediated vasodilatation in mesenteric arteries from streptozotocin-induced type 2 diabetic rats and that from normal rats incubated with advanced glycation end products (AGEs) for 3 hours. In cultured human umbilical vein endothelial cells (HUVECs), 1 ?M metformin reversed AGE-induced increase of ROS and attenuated AGE- and H2O2- induced downregulation of IKCa and SKCa after long-term incubation (>24 hours). Short-term treatment (3 hours) with 1 ?M metformin reversed the decrease of IKCa and SKCa currents induced by AGE incubation for 3 hours without changing the channel expression or the AMPK activation in HUVECs. These results are the first to demonstrate that metformin restored IKCa- and SKCa-mediated vasodilatation impaired by AGEs in rat mesenteric artery, in which the upregulation of channel activity and protein expression is likely involved.
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Assessing technical performance in differential gene expression experiments with external spike-in RNA control ratio mixtures.
Nat Commun
PUBLISHED: 08-11-2014
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There is a critical need for standard approaches to assess, report and compare the technical performance of genome-scale differential gene expression experiments. Here we assess technical performance with a proposed standard 'dashboard' of metrics derived from analysis of external spike-in RNA control ratio mixtures. These control ratio mixtures with defined abundance ratios enable assessment of diagnostic performance of differentially expressed transcript lists, limit of detection of ratio (LODR) estimates and expression ratio variability and measurement bias. The performance metrics suite is applicable to analysis of a typical experiment, and here we also apply these metrics to evaluate technical performance among laboratories. An interlaboratory study using identical samples shared among 12 laboratories with three different measurement processes demonstrates generally consistent diagnostic power across 11 laboratories. Ratio measurement variability and bias are also comparable among laboratories for the same measurement process. We observe different biases for measurement processes using different mRNA-enrichment protocols.
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Caspase-3 inhibition prevents the development of hepatopulmonary syndrome in common bile duct ligation rats by alleviating pulmonary injury.
Liver Int.
PUBLISHED: 08-11-2014
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Common bile duct ligation (CBDL) rats is an accepted experimental model of hepatopulmonary syndrome (HPS), defined as liver disease and intrapulmonary vascular dilatation and hypoxaemia. Pulmonary Akt and ERK activation followed by angiogenesis in the later stages of CBDL, contribute to the pathogenesis of HPS. However, the mechanisms behind Akt and ERK activation remain undefined. Pulmonary injury induced by increased bilirubin, endotoxin and inflammatory mediators occurs in the early stages of CBDL. We assessed the effects of relieving pulmonary injury on Akt and ERK activation and on the development of HPS following CBDL.
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The dose-dependence biological effect of laser fluence on rabbit fibroblasts derived from urethral scar.
Lasers Med Sci
PUBLISHED: 08-10-2014
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Two-micrometer laser vaporization resection has been used in clinic for years, but some patients received the treatment are still faced with excessive and abnormal wound repair which leads to the recurrent of urethral stricture eventually. Fibroblasts play a key role in the processes of "narrow-expansion/operation-restenosis" recurring problems. Here, we investigated the effect of laser fluence biomodulation on urethral scar fibroblasts as well as the underlying mechanism. Urethral scar fibroblasts were isolated and cultured, and laser irradiation (2 ?m) was applied at different laser fluence or doses (0, 0.125, 0.5, 2, 8, 32 J/cm(2)) with a single exposure in 1 day. The effect of 2-?m laser irradiation on cell proliferation, viability, and expression of scar formation related genes were investigated. Two-micrometer laser irradiation with intermediate dose (8 J/cm(2)) promoted scar fibroblasts proliferation and reactive oxygen species (ROS) production, while higher doses of 32 J/cm(2) are suppressive as it decreased the survival rate, viability, and proliferation of fibroblasts. In addition, qRT-PCR and Western blotting results both proven that collagen type I, collagen IV, MMP9, and CTGF display significant increase, yet the TGF-?1 expression was severely reduced at intermediate dose (8 J/cm(2)) group when compared with the others groups. Our findings suggest the scar formation-related genes are sensitive to intermediate laser irradiation dose, the most in scar fibroblasts. We revealed the bioeffect and molecular mechanism of 2-?m laser irradiation on rabbit urethral scar fibroblasts. Our study provides new insights into the mechanisms which involved in the excessive and abnormal wound repair of 2-?m laser vaporization resection. These results could potentially contribute to further study on biological effects and application of 2-?m laser irradiation in urethral stricture therapy.
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Synthesis and discovery of 18?-GAMG as anticancer agent in vitro and in vivo via down expression of protein p65.
Sci Rep
PUBLISHED: 08-08-2014
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Glycyrrhizic acid (GA) is a natural product with favorable antitumor activity. But, glycyrrhetinic acid monoglucuronide (GAMG) showed stronger antitumor activity than GA. It is of our interest to generate and identify novel compounds with regulation telomerase for cancer therapy. So, in this study, 18?-GAMG was synthesized via biotransformation. In vitro studies showed that it displayed potent anticancer activity and high selectivity on tumor liver cell SMMC-7721 versus human normal liver cell L-02. The further results in vivo confirmed that it could significantly improve pathological changes of N,N-diethylnitrosamine (DEN)-induced rat hepatic tumor. Western blot and immunofluorescence results indicated that the expression of p65-telomerase reverse transcriptase (TERT) was clearly down-regulated treated with it. Taken together, this study for the first time identified an active compound with high selectivity on tumor liver cell in mice. Furthermore, the title compound could inhibit the expression of protein p65 and TERT. These data support further studies to assess the rational design of more efficient p65 modulators in the future.
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Releasing of Tourniquet Before Wound Closure or not in Total Knee Arthroplasty: A Meta-Analysis of Randomized Controlled Trials.
J Arthroplasty
PUBLISHED: 08-07-2014
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The purpose of this study is to examine our hypothesis that releasing tourniquet intraoperatively before wound closure is better than releasing postoperatively after wound closure and bandaging. We carried out a systematic review using meta-analysis of selected randomized controlled trials comparing tourniquet releasing before and after wound closure in TKA. The results showed that tourniquet releasing before wound closure significantly increased the total blood loss (P<0.00001), calculated blood loss (P<0.0001) as well as postoperative blood loss (P=0.007). However, it decreased the risk of both minor (P=0.0007) and major complications (P=0.05). The available evidence indicated that releasing tourniquet before wound closure for hemostasis increased perioperative blood loss, nevertheless, the risk of complications decreased significantly.
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Development and validation of a multiplex reverse transcription PCR assay for simultaneous detection of three papaya viruses.
Viruses
PUBLISHED: 08-06-2014
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Papaya ringspot virus (PRSV), Papaya leaf distortion mosaic virus (PLDMV), and Papaya mosaic virus (PapMV) produce similar symptoms in papaya. Each threatens commercial production of papaya on Hainan Island, China. In this study, a multiplex reverse transcription PCR assay was developed to detect simultaneously these three viruses by screening combinations of mixed primer pairs and optimizing the multiplex RT-PCR reaction conditions. A mixture of three specific primer pairs was used to amplify three distinct fragments of 613 bp from the P3 gene of PRSV, 355 bp from the CP gene of PLDMV, and 205 bp from the CP gene of PapMV, demonstrating the assay's specificity. The sensitivity of the multiplex RT-PCR was evaluated by showing plasmids containing each of the viral target genes with 1.44 × 103, 1.79 × 103, and 1.91 × 102 copies for the three viruses could be detected successfully. The multiplex RT-PCR was applied successfully for detection of three viruses from 341 field samples collected from 18 counties of Hainan Island, China. Rates of single infections were 186/341 (54.5%), 93/341 (27.3%), and 3/341 (0.9%), for PRSV, PLDMV, and PapMV, respectively; 59/341 (17.3%) of the samples were co-infected with PRSV and PLDMV, which is the first time being reported in Hainan Island. This multiplex RT-PCR assay is a simple, rapid, sensitive, and cost-effective method for detecting multiple viruses in papaya and can be used for routine molecular diagnosis and epidemiological studies in papaya.
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A time course study about gene expression of post-thermal injury with DNA microarray.
Int. J. Dermatol.
PUBLISHED: 07-30-2014
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Burn injury is one of the most common and devastating forms of trauma in daily life. However, the exact sequence of events after burn injury remains unknown.
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Survivin-targeting Artificial MicroRNAs Mediated by Adenovirus Suppress Tumor Activity in Cancer Cells and Xenograft Models.
Mol Ther Nucleic Acids
PUBLISHED: 07-24-2014
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Survivin is highly expressed in most human tumors and fetal tissue, and absent in terminally differentiated cells. It promotes tumor cell proliferation by negatively regulating cell apoptosis and facilitating cell division. Survivin's selective expression pattern suggests that it might be a suitable target for cancer therapy, which would promote death of transformed but not normal cells. This was tested using artificial microRNAs (amiRNAs) targeting survivin. After screening, two effective amiRNAs, which knocked down survivin expression, were identified and cloned into a replication-defective adenoviral vector. Tumor cells infected with the recombinant vector downregulated expression of survivin and underwent apoptotic cell death. Further studies showed that apoptosis was associated with increases in caspase 3 and cleaved Poly (ADP-ribose) polymerase, and activation of the p53 signaling pathway. Furthermore, amiRNA treatment caused blockade of mitosis and cell cycle arrest at the G2/M phase. In vivo, survivin-targeting amiRNAs expressed by adenoviral vectors effectively delayed growth of hepatocellular and cervical carcinomas in mouse xenograft models. These results indicate that silencing of survivin by amiRNA has potential for treatment of cancer.
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On Thompson's conjecture for alternating groups A p+3.
ScientificWorldJournal
PUBLISHED: 07-22-2014
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Let G be a group. Denote by ?(G) the set of prime divisors of |G|. Let GK(G) be the graph with vertex set ?(G) such that two primes p and q in ?(G) are joined by an edge if G has an element of order p · q. We set s(G) to denote the number of connected components of the prime graph GK(G). Denote by N(G) the set of nonidentity orders of conjugacy classes of elements in G. Alavi and Daneshkhah proved that the groups, A n where n = p, p + 1, p + 2 with s(G) ? 2, are characterized by N(G). As a development of these topics, we will prove that if G is a finite group with trivial center and N(G) = N(A p+3) with p + 2 composite, then G is isomorphic to A p+3.
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High efficiency photocatalysis for pollutant degradation with MoS2/C3N4 heterostructures.
Langmuir
PUBLISHED: 07-18-2014
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Porous graphitic carbon nitride was synthesized by controllable thermal polymerization of urea in air. Their textural, electrical, and optical properties were tuned by varying the heating rate. The presence of proper residual oxygen in carbon nitride matrix had enhanced light absorption and inhibited the recombination of charge carriers. Furthermore, the MoS2 nanosheets were coupled into the carbon nitride to form MoS2/C3N4 heterostructures via a facile ultrasonic chemical method. The optimized MoS2/C3N4 heterostructure with 0.05 wt % MoS2 showed a reaction rate constant as high as 0.301 min(-1), which was 3.6 times that of bare carbon nitride. As analyzed by SEM, TEM, UV-vis absorption, PL and photoelectrochemical measurements, intimate contact interface, extended light response range, enhanced separation speed of charge carriers, and high photocurrent density upon MoS2 coupling led to the photocatalytic promotion of the MoS2/C3N4 heterostructures. In this architecture, MoS2 served as electron trapper to extend the lifetime of separated electron-hole pairs. Meanwhile, the accumulated holes on the surface of carbon nitride oxidized the organic dye directly, which was a predominant process in the photodegradation of organic pollutants in water treatment. The promotional mechanisms and principles reported here would have great significance in heterogeneous photocatalysis.
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[Structural characteristics and biocompatibility of a new nano-Ta-Ti alloy rod fabricated by laser melting technique].
Nan Fang Yi Ke Da Xue Xue Bao
PUBLISHED: 06-28-2014
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To evaluate the structural characteristics and biocompatibility of a novel nano-Ta-Ti alloy rod for its potential application in internal fixation.
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Lack of association between LEPR Lys656Asn or Ser343Ser polymorphisms and cancer susceptibility: A meta-analysis.
Biomed Rep
PUBLISHED: 06-26-2014
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Previous studies have shown conflicting results between the association of leptin receptor (LEPR) genetic polymorphisms and cancer risk. The frequent LEPR Lys656Asn or Ser343Ser genetic polymorphism has been demonstrated to be functional and may promote genetic susceptibility to cancers. However, the association between the LEPR Lys656Asn or Ser343Ser genetic polymorphism and cancer risk remains to be determined. To improve the understanding of the LEPR Lys656Asn or Ser343Ser genetic polymorphism role in global cancer, a comprehensive meta-analysis was conducted that comprised 2,480 cases and 3,162 controls. The LEPR Lys656Asn or Ser343Ser genetic polymorphism did not significantly affect the cancer risk. In the stratified analysis, there was no significant association of the LEPR Lys656Asn or Ser343Ser variants with any type of cancer under any model. In addition, significantly increased risks were found in the Asian population in heterozygous codominant [odds ratio (OR), 1.24 (1.01-1.53)] and dominant [OR, 1.24 (1.02-1.50)] genetic models. A significantly increased susceptibility to cancer was not found when stratified by study design. There were no significant differences found in genotype method and sample size in cases among the genotypes. These findings indicated a lack of association between LEPR Lys656Asn or Ser343Ser polymorphisms and cancer susceptibility, however, these polymorphisms may increase the cancer susceptibility among the Asian population, particularly in the dominant genetic model. The single-nucleotide polymorphism is also suggested to function as a dominant mutation, which requires verification or association with functional studies.
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[Cloning and gene expression of acetyl-CoA C-acetyl transferase gene (AsAACT) from Aquilaria sinensis].
Zhongguo Zhong Yao Za Zhi
PUBLISHED: 06-25-2014
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This study aimed to clone the acetyl-CoA C-acetyl transferase (AACT) gene from Aquilaria sinensis and analyze the bioinformatics and expression of the gene.
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Hierarchical Zn/Ni-MOF-2 Nanosheet-Assembled Hollow Nanocubes for Multicomponent Catalytic Reactions.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 06-23-2014
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Metal-organic frameworks (MOFs) are potentially useful molecular materials that can exhibit structure flexibilities induced by some external stimuli. Such structure transformations can furnish MOFs with improved properties. The shape-controlled growth of MOFs combined with crystal-structure transformation is rarely achieved. Herein, we demonstrate the synthesis of hierarchical Zn/Ni-MOF-2 nanosheet-assembled hollow nanocubes (NAHNs) by a facile surfactant-free solvothermal approach. The unique nanostructures undergo crystal-structure transformation from Zn/Ni-MOF-5 nanocubes to Zn/Ni-MOF-2 nanosheets, which is analogous to the dissolution and recrystallization of inorganic nanocrystals. The present synthetic strategy to fabricate isostructural MOFs with hierarchical, hollow, and bimetallic nanostructures is expected to expand the diversity and range of potential applications of MOFs.
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Suppression of the xCT-CD44v antiporter system sensitizes triple-negative breast cancer cells to doxorubicin.
Breast Cancer Res. Treat.
PUBLISHED: 06-11-2014
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The xCT antiporter is known to be upregulated in 30 % of triple-negative breast cancer (TNBC) cell lines. The xCT-CD44 variant (CD44v) system regulates the levels of reactive oxygen species (ROS) in cancer cells and promotes tumor growth. Here, the role of this antiporter system in relation to chemotherapy was evaluated. MDA-MB-231 and MDA-MB-436 cells were transfected with lentiviral vectors expressing short hairpin RNA against xCT or CD44v. Following doxorubicin treatment, cellular proliferation was monitored, ROS were measured, and intracellular levels of cysteine and glutathione (GSH) were determined using liquid chromatography-mass spectrometry. A TNBC orthotopic tumor model was used to evaluate the impact of xCT-CD44v inhibition on doxorubicin efficacy in vivo. Doxorubicin treatment of TNBC cells caused increased expression of xCT through upregulation of CD44v. Consequently, the intracellular uptake of cystine increased, enabling rapid synthesis of GSH, and neutralization of doxorubicin-induced ROS. Suppression of xCT or CD44v impaired the defense against drug-induced oxidative stress, thereby sensitizing cells to doxorubicin. The importance of the xCT-CD44v in supporting tumor growth during doxorubicin treatment was also demonstrated in an in vivo tumor model of TNBC. These findings suggest that the antiporter system could serve as a target for increasing the anticancer efficacy of conventional therapy in patients with TNBC.
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Log-Gabor energy based multimodal medical image fusion in NSCT domain.
Comput Math Methods Med
PUBLISHED: 06-07-2014
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Multimodal medical image fusion is a powerful tool in clinical applications such as noninvasive diagnosis, image-guided radiotherapy, and treatment planning. In this paper, a novel nonsubsampled Contourlet transform (NSCT) based method for multimodal medical image fusion is presented, which is approximately shift invariant and can effectively suppress the pseudo-Gibbs phenomena. The source medical images are initially transformed by NSCT followed by fusing low- and high-frequency components. The phase congruency that can provide a contrast and brightness-invariant representation is applied to fuse low-frequency coefficients, whereas the Log-Gabor energy that can efficiently determine the frequency coefficients from the clear and detail parts is employed to fuse the high-frequency coefficients. The proposed fusion method has been compared with the discrete wavelet transform (DWT), the fast discrete curvelet transform (FDCT), and the dual tree complex wavelet transform (DTCWT) based image fusion methods and other NSCT-based methods. Visually and quantitatively experimental results indicate that the proposed fusion method can obtain more effective and accurate fusion results of multimodal medical images than other algorithms. Further, the applicability of the proposed method has been testified by carrying out a clinical example on a woman affected with recurrent tumor images.
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Intrathecal siRNA Against GPNMB Attenuates Nociception in a Rat Model of Neuropathic Pain.
J. Mol. Neurosci.
PUBLISHED: 06-01-2014
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Neuropathic pain is characterized by hyperalgesia, allodynia, and spontaneous pain. Recent studies have shown that glycoprotein nonmetastatic melanoma B (GPNMB) plays a pivotal role in neuronal survival and neuroprotection. However, the role of GPNMB in neuropathic pain remains unknown. The aim of the present study was to assess the role of GPNMB in neuropathic pain. In cultured spinal cord neurons, we used two small interfering RNAs (siRNAs) targeting the complementary DNA (cDNA) sequence of rat GPNMB that had potent inhibitory effects on GPNMB, and siRNA1-GPNMB was selected for further in vivo study as it had the higher inhibitory effect. After sciatic nerve injury in rats, the endogenous level of GPNMB was increased in a time-dependent manner in the spinal cord. Furthermore, the intrathecal injection of siRNA1-GPNMB inhibited the expression of GPNMB and pro-inflammatory factors (TNF-?, IL-1?, and IL-6) and alleviated mechanical allodynia and thermal hyperalgesia in the chronic constriction injury (CCI) model of rats. Taken together, our findings suggest that siRNA against GPNMB can alleviate the chronic neuropathic pain caused by CCI, and this effect may be mediated by attenuated expression of TNF-?, IL-1?, and IL-6 in the spinal cord of CCI rats. Therefore, inhibition of GPNMB may provide a novel strategy for the treatment of neuropathic pain.
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Near-infrared-emitting two-dimensional codes based on lattice-strained core/(doped) shell quantum dots with long fluorescence lifetime.
Adv. Mater. Weinheim
PUBLISHED: 05-27-2014
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Lattice-strained CdTe/CdS:Cu quantum dots (QDs) with a widely tunable near-infrared (NIR) fluorescence emission spectrum (700-910 nm) and long lifetime (up to 1 ?s) are synthesized. Based on the multiemission and multi-lifetime of the well-defined QDs, NIR-emitting two-dimensional (2D) codes are achieved by embedding as-prepared QDs into agarose beads. This provides a new strategy for fluorescent 2D codes.
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Safety of Nanoparticles in Medicine.
Curr Drug Targets
PUBLISHED: 05-16-2014
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Nanomedicine involves the use of nanoparticles for therapeutic and diagnostic purposes. During the past two decades, a growing number of nanomedicines have received regulatory approval and many more show promise for future clinical translation. In this context, it is important to evaluate the safety of nanoparticles in order to achieve biocompatibility and desired activity. However, it is unwarranted to make generalized statements regarding the safety of nanoparticles, since the field of nanomedicine comprises a multitude of different manufactured nanoparticles made from various materials. Indeed, several nanotherapeutics that are currently approved, such as Doxil and Abraxane, exhibit fewer side effects than their small molecule counterparts, while other nanoparticles (e.g. metallic and carbon-based particles) tend to display toxicity. However, the hazardous nature of certain nanomedicines could be exploited for the ablation of diseased tissue, if selective targeting can be achieved. This review discusses the mechanisms for molecular, cellular, organ, and immune system toxicity, which can be observed with a subset of nanoparticles. Strategies for improving the safety of nanoparticles by surface modification and pretreatment with immunomodulators are also discussed. Additionally, important considerations for nanoparticle safety assessment are reviewed. In regards to clinical application, stricter regulations for the approval of nanomedicines might not be required. Rather, safety evaluation assays should be adjusted to be more appropriate for engineered nanoparticles.
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Quantitative trait Loci mapping for bacterial blight resistance in rice using bulked segregant analysis.
Int J Mol Sci
PUBLISHED: 05-15-2014
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Oryza meyeriana is highly resistant to rice bacterial blight (BB) and this resistance trait has been transferred to cultivated rice (O. sativa) using asymmetric somatic hybridization. However, no resistance genes have yet been cloned. In the present study, a progeny of the somatic hybridization with high BB resistance was crossed with a rice cultivar with high BB susceptibility to develop an F2 population. Using bulked segregant analysis (BSA), 17 polymorphic markers that were linked to rice BB resistance were obtained through scanning a total of 186 simple sequence repeats (SSR) and sequence-tagged site (STS) markers, evenly distributed on 12 chromosomes. A genetic linkage map was then constructed based on the 17 linkage markers and the F2 segregating population, which was followed by mapping for quantitative trait loci (QTLs) for BB resistance. Three QTLs were identified on chromosomes 1, 3 and 5, respectively, and the alleles of the resistant parent at any of the QTLs increased BB resistance. All of the three QTLs had a strong effect on resistance, explaining about 21.5%, 12.3% and 39.2% of the resistance variance, respectively. These QTLs were different from the loci of the BB resistance genes that have been identified in previous studies. The QTLs mapped in this work will facilitate the isolation of novel BB resistance genes and their utilization in rice resistance breeding.
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Synthesis of caffeic acid amides bearing 2,3,4,5-tetra-hydrobenzo[b][1,4]dioxocine moieties and their biological evaluation as antitumor agents.
Molecules
PUBLISHED: 05-04-2014
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A series of caffeic acid amides D1-D17 bearing 2,3,4,5-tetrahydrobenzo-[b][1,4]dioxocine units has been synthesized and their biological activities evaluated for potential antiproliferative and EGFR inhibitory activity. Of all the compounds studied, compound D9 showed the most potent inhibitory activity (IC50=0.79 ?M for HepG2 and IC50=0.36 ?M for EGFR). The structures of compounds were confirmed by 1H-NMR, ESI-MS and elemental analysis. Among all, the structure of compound D9 ((E)-N-(4-ethoxyphenyl)-3-(2,3,4,5-tetrahydrobenzo[b][1,4]dioxocin-8-yl)acrylamide) was also determined by single-crystal X-ray diffraction analysis. Compound D9 was found to be a potential antitumor agent according to biological activity, molecular docking, apoptosis assay and inhibition of HepG2.
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Luciferase reporter cells as a platform to detect SMAD-dependent collagen production.
J. Biosci. Bioeng.
PUBLISHED: 04-20-2014
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Aberrant collagen production can lead to many diseases such as fibrosis. Current methods of collagen detection are insensitive, time-consuming and laborious. We have developed a rapid, sensitive assay using chemiluminescence-based reporter cell system. Stable 3T3/NIH-SMAD-luciferase cells were generated for detection of collagen expression through TGF-? signaling, a major fibrogenic pathway. We demonstrated that these reporter cells could be used as a rapid screening tool for detection of SMAD-dependent collagen production with higher sensitivity than existing assays. Flexibility of this cell-based assay in different detection platforms makes it attractive for high throughput screening of potential fibrogenic agents and drug candidates.
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Long-term follow-up of sigmoid bladder augmentation for low-compliance neurogenic bladder.
Urology
PUBLISHED: 04-17-2014
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To assess the clinical and urodynamic outcomes of patients with low-compliance neurogenic bladder who were treated with sigmoid bladder augmentation (SBA) over a long-term follow-up.
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Synthesis, molecular docking and biological evaluation of glycyrrhizin analogs as anticancer agents targeting EGFR.
Molecules
PUBLISHED: 04-10-2014
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Glycyrrhizin (GA) analogs in the form of 3-glucuronides and 18-epimers were synthesized and their anticancer activities were evaluated. Alkaline isomerization of monoglucuronides is reported. In vitro and in vivo studies showed that glycyrrhetinic acid monoglucuronides (GAMGs) displayed higher anticancer activities than those of bisglucuronide GA analogs, while anticancer activity of the 18?-epimer was superior to that of the 18?-epimer. 18?-GAMG was firstly nicely bound to epidermal growth factor receptor (EGFR) via six hydrogen bonds and one charge interaction, and the docking calculation proved the correlation between anticancer activities and EGFR inhibitory activities. Highly active 18?-GAMG is thus of interest for the further studies as a potential anticancer agent.
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Recent progress in research on high-voltage electrolytes for lithium-ion batteries.
Chemphyschem
PUBLISHED: 03-27-2014
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Developing a stable and safe electrolyte that works at voltages as high as 5 V is a formidable challenge in present Li-ion-battery research because such high voltages are beyond the electrochemical stability of the conventional carbonate-based solvents available. In the past few years, extensive efforts have been carried out by the research community toward the exploration of high-voltage electrolytes. In this review, recent progress in the study of several promising high-voltage electrolyte systems, as well as their recipes, electrochemical performance, electrode compatibility, and characterization methods, are summarized and reviewed. These new electrolyte systems include high-voltage film-forming additives and new solvents, such as sulfones, ionic liquids, nitriles, and fluorinated carbonates. It appears to be very difficult to find a good high-voltage (?5 V) electrolyte with a single-component solvent at the present stage. Using mixed fluorinated-carbonate solvents and additives are two realistic solutions for practical applications in the near term, while sulfones, nitriles, ionic liquids and solid-state electrolyte/polymer electrolytes are promising candidates for the next generation of high-voltage electrolyte systems.
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[Effects of stanniocalcin-1 and hypoxia-inducible factor-1? on mitochondrial membrane potential stability in renal carcinoma cells].
Zhongguo Yi Xue Ke Xue Yuan Xue Bao
PUBLISHED: 03-04-2014
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To explore the effects of stanniocalcin-1(STC-1)and hypoxia-inducible factor-1?(HIF-1?)on the calcium and thus on the mitochondrial membrane potential(??m)in renal carcinoma cells.
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Iodine-125 induces apoptosis via regulating p53, microvessel density, and vascular endothelial growth factor in colorectal cancer.
World J Surg Oncol
PUBLISHED: 02-07-2014
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Iodine interstitial brachytherapy has been widely reported for treating colorectal cancer (CRC). However, the inhibitory molecular mechanism of iodine-125 (I-125) on CRC has not been reported.
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Recent androgen receptor antagonists in prostate cancer.
Mini Rev Med Chem
PUBLISHED: 02-02-2014
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Androgen receptor has been shown to promote prostate cell growth and carcinogenesis of prostate cancer by up-regulating its target genes. Testosterone and dihydrotestosterone are two major hormones which bind to and activate androgen receptor. Targeting both the androgen receptor and the enzymes catalyzing the biosynthesis of testosterone and dihydrotestosterone has been shown to be clinically beneficial in the treatment of prostate cancer. Prostate cancer can become castration-resistant after long term treatment with chemo drugs, so efforts in finding compounds with improved efficiency to castration-resistant prostate cancer are urgently needed. In this review we summarized the studies on recent progress in the development of small molecular AR antagonists for the treatment of prostate cancer.
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Impact of selenium supply on Se-methylselenocysteine and glucosinolate accumulation in selenium-biofortified Brassica sprouts.
Food Chem
PUBLISHED: 01-20-2014
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Brassica sprouts are widely marketed as functional foods. Here we examined the effects of Se treatment on the accumulation of anticancer compound Se-methylselenocysteine (SeMSCys) and glucosinolates in Brassica sprouts. Cultivars from the six most extensively consumed Brassica vegetables (broccoli, cauliflower, green cabbage, Chinese cabbage, kale, and Brussels sprouts) were used. We found that Se-biofortified Brassica sprouts all were able to synthesize significant amounts of SeMSCys. Analysis of glucosinolate profiles revealed that each Brassica crop accumulated different types and amounts of glucosinolates. Cauliflower sprouts had high total glucosinolate content. Broccoli sprouts contained high levels of glucoraphanin, a precursor for potent anticancer compound. Although studies have reported an inverse relationship between accumulation of Se and glucosinolates in mature Brassica plants, Se supply generally did not affect glucosinolate accumulation in Brassica sprouts. Thus, Brassica vegetable sprouts can be biofortified with Se for the accumulation of SeMSCys without negative effects on chemopreventive glucosinolate contents.
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Comparison of conventional RT-PCR, reverse-transcription loop-mediated isothermal amplification, and SYBR green I-based real-time RT-PCR in the rapid detection of bovine viral diarrhea virus nucleotide in contaminated commercial bovine sera batches.
J. Virol. Methods
PUBLISHED: 01-10-2014
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Bovine viral diarrhea virus (BVDV) can contaminate biological products produced in bovine or porcine cells or manufactured using bovine sera. A rapid, specific, sensitive, and practical method of detecting BVDV in bio-products is needed. The purpose of this study was to compare three assays with respect to their ability to accurately detect BVDV in biological samples, namely reverse-transcription loop-mediated isothermal amplification (RT-LAMP), SYBR green I-based real-time RT-PCR, and conventional RT-PCR. All assays detected BVDV nucleotide and differentiated between BVDV-free and -contaminated bovine sera successfully. In addition, the results were specific to BVDV: the amplification of samples containing the closely related classical swine fever virus or other pathogenic bovine viruses yielded negative results. The lowest detection threshold, 10(1) copies, was displayed by the SYBR green I-based real-time RT-PCR and RT-LAMP assay. This assay was also the most effective in the detection of BVDV contamination in a set of commercially available bovine sera. The field conditions suggest that RT-LAMP is specific and sensitive to detecting BVDV in biological samples and may be used for quality control of biomaterials.
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Synthesis and biological evaluation of compounds which contain pyrazole, thiazole and naphthalene ring as antitumor agents.
Bioorg. Med. Chem. Lett.
PUBLISHED: 01-09-2014
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A series of compounds which contain pyrazole, thiazole and naphthalene ring (1a-7a, 1b-7b, 1c-7c, 1d-7d) were firstly synthesized and their anti-proliferative activity, EGFR inhibitory activity, cytotoxicity and inhibition to Hela cell migration were evaluated. Compound 2-(3-(3,4-dimethylphenyl)-5-(naphthalen-2-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4(5H)-one (7d) displayed the most potent inhibitory activity (IC50=0.86?M for Hela and IC50=0.12?M for EGFR). Structure-activity relationship (SAR) analysis showed that the anti-proliferative activity was affected by A-ring-substituent (-OCH3>-CH3>-H>-Br>-Cl>-F). Docking simulation of compound 7d into EGFR active site showed that naphthalene ring of 7d with LYS721 formed two p-? bonds, which enhanced antitumor activity. Therefore, compound 7d may be developed as a potential antitumor agent.
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Polymorphism, Expression of Natural Resistance-associated Macrophage Protein 1 Encoding Gene (NRAMP1) and Its Association with Immune Traits in Pigs.
Asian-australas. J. Anim. Sci.
PUBLISHED: 01-08-2014
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Natural resistance-associated macrophage protein 1 encoding gene (NRAMP1) plays an important role in immune response against intracellular pathogens. To evaluate the effects of NRAMP1 gene on immune capacity in pigs, tissue expression of NRAMP1 mRNA was observed by real time quantitative polymerase chain reaction (PCR), and the results revealed NRAMP1 expressed widely in nine tissues. One single nucleotide polymorphism (SNP) (ENSSSCG00000025058: g.130 C>T) in exon1 and one SNP (ENSSSCG00000025058: g.657 A>G) in intron1 region of porcine NRAMP1 gene were demonstrated by DNA sequencing and PCR-RFLP analysis. A further analysis of SNP genotypes associated with immune traits including contain of white blood cell (WBC), granulocyte, lymphocyte, monocyte (MO), rate of cytotoxin in monocyte (MC) and CD4/CD8 T lymphocyte subpopulations in blood was carried out in four pig populations including Large White and three Chinese indigenous breeds (Wannan Black, Huai pig and Wei pig). The results showed that the SNP (ENSSSCG00000025058: g.130 C>T) was significantly associated with level of WBC % (p = 0.031), MO% (p = 0.024), MC% (p = 0.013) and CD4(-)CD8(+) T lymphocyte (p = 0.023). The other SNP (ENSSSCG00000025058: g.657 A>G) was significantly associated with the level of MO% (p = 0.012), MC% (p = 0.019) and CD4(-)CD8(+) T lymphocyte (p = 0.037). These results indicate that the NRAMP1 gene can be regarded as a molecular marker for genetic selection of disease susceptibility in pig breeding.
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Synthesis, and antibacterial activity of novel 4,5-dihydro-1H-pyrazole derivatives as DNA gyrase inhibitors.
Org. Biomol. Chem.
PUBLISHED: 01-03-2014
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A series of novel 4,5-dihydropyrazole derivatives (4a-4t), containing the dinitrobenzotrifluoride moiety, as DNA gyrase inhibitors were designed and synthesized. Based on the preliminary results, compounds 4d, 4f and 4t with potent inhibitory activity in bacterial growth may be wonderful antibacterial agents; among them, compound 4t displayed the most potent activity with minimum inhibitory concentration (MIC) values of 3.125, 0.39, 0.39 and 0.39 ?g mL(-1) against Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli respectively, which was comparable with penicillin and kanamycin B with corresponding MIC values of 3.125, 3.125, 0.39, 0.39 ?g mL(-1) and 1.562, 1.562, 1.562, 1.562 ?g mL(-1), respectively. In particular, compound 4d showed the most potent anti-Gram-positive bacterial activity with a MIC value of 0.39 ?g mL(-1) against the tested Gram-positive bacterial strains and exhibited the most potent B. subtilis DNA gyrase and S. aureus DNA gyrase inhibitory activity with an IC50 of 0.125 ?g mL(-1). Docking simulation was performed to insert compound 4d into the S. aureus DNA gyrase active site to determine the probable binding conformation.
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A Novel Algorithm to Enhance P300 in Single Trials: Application to Lie Detection Using F-Score and SVM.
PLoS ONE
PUBLISHED: 01-01-2014
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The investigation of lie detection methods based on P300 potentials has drawn much interest in recent years. We presented a novel algorithm to enhance signal-to-noise ratio (SNR) of P300 and applied it in lie detection to increase the classification accuracy. Thirty-four subjects were divided randomly into guilty and innocent groups, and the EEG signals on 14 electrodes were recorded. A novel spatial denoising algorithm (SDA) was proposed to reconstruct the P300 with a high SNR based on independent component analysis. The differences between the proposed method and our/other early published methods mainly lie in the extraction and feature selection method of P300. Three groups of features were extracted from the denoised waves; then, the optimal features were selected by the F-score method. Selected feature samples were finally fed into three classical classifiers to make a performance comparison. The optimal parameter values in the SDA and the classifiers were tuned using a grid-searching training procedure with cross-validation. The support vector machine (SVM) approach was adopted to combine with an F-score because this approach had the best performance. The presented model F-score_SVM reaches a significantly higher classification accuracy for P300 (specificity of 96.05%) and non-P300 (sensitivity of 96.11%) compared with the results obtained without using SDA and compared with the results obtained by other classification models. Moreover, a higher individual diagnosis rate can be obtained compared with previous methods, and the presented method requires only a small number of stimuli in the real testing application.
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[Adsorption characteristics of f2 bacteriophages by four substrates in constructed wetland].
Huan Jing Ke Xue
PUBLISHED: 12-25-2013
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Performance of f2 phages adsorption by four substrates including anthracite coal, steel slag, zeolite and forsterite was investigated through batch and dynamic experiments. Results of batch experiments showed that the removal efficiency of f2 phages by these four substrates was in the order of anthracite > steel slag > forsterite approximately zeolite. The adsorption of f2 phages by anthracite experienced fast, medium and slow stages, and the removal efficiency of f2 phages increased gradually with the increase of anthracite dosage, e. g. the optimized dosage of anthracite was 8.0 g at a solid/liquid ratio of 1:12.5 (m/V). The isothermal adsorption of all four substrates was described with Freundlich and Langmuir isothermal adsorption equation very well, and the adsorption of f2 phages by both anthracite and steel slag fitted pseudo-second order adsorption kinetics at their theoretical adsorption capacities of 3. 35 x 10(8) PFU.g-1 and 2.56 x 10(8) PFU.g-1, respectively, nearly the same as the equilibrium adsorption capacities obtained under the experiment conditions. And the liquid diffusion process was a rate-limiting step of the adsorption of f2 phage by both anthracite and steel slag, but not the only one. The results of dynamic adsorption experiments showed that the adsorption process of f2 phages in the three adsorption columns including anthracite, steel slag and zeolite experienced four stages of adaption, adsorption, pulse adsorption and adsorption equilibrium, and the total removal rates of f2 phages were more than 2. 55 Ig.
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Surgical treatment of 42 patients with cerebral schistosomiasis caused by Schistosoma japonicum.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi
PUBLISHED: 12-24-2013
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To investigate the clinical value of surgical treatment for cerebral schistosomiasis.
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Global and local brain network reorganization in attention-deficit/hyperactivity disorder.
Brain Imaging Behav
PUBLISHED: 12-17-2013
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Brain is a complex network with an anatomical and functional organization. The differences in brain organization of those with attention-deficit/hyperactivity disorder (ADHD) are still not well understood. Here, we study brain organization in ADHD subjects using a complex network derived from resting-state functional magnetic resonance imaging (fMRI) data of ADHD and normal subjects. Our results reveal that the brain networks of ADHD subjects are reorganized compared to those without ADHD in global and local brain functional networks. We find that the ADHD subjects show decreasing brain network integration and increasing brain network segregation. More interestingly, we find similarities of brain topology properties between local and global brain networks. Our finding indicates that cognitive dysfunction in ADHD is probably associated with disrupted global and local brain network topological properties. Our results can help us understand the pathophysiological mechanism of ADHD and serve as a sensitive and specific biomarker of ADHD.
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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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Simultaneous reduction of radiation dose and scatter for CBCT by using collimators.
Med Phys
PUBLISHED: 12-11-2013
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Purpose: On-board cone-beam CT (CBCT) imaging has been widely available in radiotherapy clinic for target localization. However, the extra radiation dose from CBCT is always a concern for its frequent use. Additionally, the relatively large scatter in CBCT often degrades the image quality. By using collimators, some of the X-rays can be stopped from reaching the patient and the detectors, hence both the scatter and the patient doses are simultaneously reduced. The authors show in this work that the collimated CBCT data can be reconstructed without any noticeable artifacts for certain collimator blocking ratios and blocking patterns, and the focus of this work is to study the relationship between the image quality and these two collimator factors.Methods: A CBCT system with collimators was simulated following the typical geometry used in clinic. Different collimator designs were tested by varying the size and the number of the collimator slits, and at the same time, the ratio of transmitted beams to total beams was varied from 100% to 10%, resulting in hundreds of different simulation scenarios. Lung and pelvis phantoms created from patients CT images were used in the simulations, and an iterative reconstruction algorithm using the compressed sensing technique was adopted. The image quality was examined by root mean square errors (RMSEs) and compared with the conventional CBCT images.Results: The CBCT image quality increases as the amount of beams passing through the collimators increases, and decreases as the size of the collimator slits increases. With ultra-high resolution collimators, the RMSEs were comparable to the conventional CBCT image quality until the beam transmission rate is reduced below 25%.Conclusions: Collimators can reduce the scatters and radiation dose, however, the collimated CBCT image quality is strongly dependent on both the collimator blocking ratio and the blocking pattern. To achieve image quality comparable to the conventional CBCT, the amount of information and data format must be adequate.
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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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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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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.