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A Novel Efficient Mn(4+) Activated Ca14Al10Zn6O35 Phosphor: Application in Red-Emitting and White LEDs.
Inorg Chem
PUBLISHED: 10-28-2014
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A new, highly efficient deep red-emitting phosphor Ca14Al10Zn6O35:Mn(4+) was developed as a component of solid-state white light-emitting diodes (LEDs). The structural and optical characterization of the phosphor is described. The phosphor exhibits strong emission in the range of 650-700 nm when excited by 460 nm excitation, with a quantum efficiency approaching 50%. Concentration dependence of Mn(4+) luminescence in Ca14Al10Zn6O35:Mn(4+) is investigated. Attempts to understand the thermal stability on the basis of the thermal quenching characteristics of Ca14Al10Zn6O35:Mn(4+) is presented. The results suggest that phosphors deriving from Ca14Al10Zn6O35:Mn(4+) have potential application for white LEDs. In addition, influence of cation substitution on the luminescence intensity of these phosphors is elucidated.
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Electrochemical, spectroscopic and theoretical studies of a simple bifunctional cobalt corrole catalyst for oxygen evolution and hydrogen production.
Phys Chem Chem Phys
PUBLISHED: 10-14-2014
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Six cobalt and manganese corrole complexes were synthesized and examined as single-site catalysts for water splitting. The simple cobalt corrole [Co(tpfc)(py)2] (1, tpfc = 5,10,15-tris(pentafluorophenyl)corrole, py = pyridine) catalyzed both water oxidation and proton reduction efficiently. By coating complex 1 onto indium tin oxide (ITO) electrodes, the turnover frequency for electrocatalytic water oxidation was 0.20 s(?1) at 1.4 V (vs. Ag/AgCl, pH = 7), and it was 1010 s(?1) for proton reduction at ?1.0 V (vs. Ag/AgCl, pH = 0.5). The stability of 1 for catalytic oxygen evolution and hydrogen production was evaluated by electrochemical, UV-vis and mass measurements, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX), which confirmed that 1 was the real molecular catalyst. Titration and UV-vis experiments showed that the pyridine group on Co dissociated at the beginning of catalysis, which was critical to subsequent activation of water. A proton-coupled electron transfer process was involved based on the pH dependence of the water oxidation reaction catalyzed by 1. As for manganese corroles 2–6, although their oxidizing powers were comparable to that of 1, they were not as stable as 1 and underwent decomposition at the electrode. Density functional theory (DFT) calculations indicated that water oxidation by 1 was feasible through a proposed catalytic cycle. The formation of an O–O bond was suggested to be the rate-determining step, and the calculated activation barrier of 18.1 kcal mol(?1) was in good agreement with that obtained from experiments.
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Ba1.3Ca0.7SiO4:Eu(2+),Mn(2+): A Promising Single-Phase, Color-Tunable Phosphor for Near-Ultraviolet White-Light-Emitting Diodes.
Inorg Chem
PUBLISHED: 09-26-2014
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In this paper, Eu(2+)-doped and Eu(2+)/Mn(2+)-codoped Ba1.3Ca0.7SiO4 phosphors were synthesized by means of a conventional solid-state reaction process. The single-phase purity was checked by means of X-ray diffraction and the Rietveld method. Under excitation at 390 nm, the emission spectra of the Eu(2+)-doped phosphors exhibit a broad-band emission centered at 500 nm caused by the electric dipole allowed transition of the Eu(2+) ions. The emission spectra of codoped phosphors show one more broad emission centered at 600 nm attributable to the transitions from the (4)T1((4)G) ? (6)A1((6)S) of Mn(2+) ions. The luminescent color of the codoped phosphors can be easily adjusted from blue to red with variation of the Mn(2+) content. The energy transfer mechanism from the Eu(2+) to Mn(2+) ions in Ba1.3Ca0.7SiO4 phosphors has been confirmed to be the resonant type via dipole-quadrupole interaction, and the critical distance has been calculated quantitatively. All these results demonstrate that the Eu(2+)/Mn(2+)-codoped Ba1.3Ca0.7SiO4 phosphors can be a promising single-phase, color-tunable phosphor for near-UV white-light-emitting diodes after a further optimization process. Additionally, a great red shift from 593 to 620 nm has been observed following the increase of Mn(2+) content, and the phenomenon has been discussed in relation to the changes in the crystal field surrounding the Mn(2+) ions and the exchange interactions caused by the formation of Mn(2+) pairs.
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?-Carotene As a Lipophilic Scavenger of Nitric Oxide.
J Phys Chem B
PUBLISHED: 09-26-2014
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The efficient bleaching following continuous bubbling of gaseous nitric oxide (NO(•)) to ?-carotene (?-Car) dissolved in n-hexane under anaerobic conditions results from an initial addition of two NO(•) followed by fragmentation coupled with further NO(•) addition as shown by mass spectrometry (MS). Density functional theory (DFT) calculations demonstrated that hydrogen atom transfer (HAT) and electron transfer (ET) from ?-Car to NO(•) are strongly energetically unfavorable in contrast to radical adduct formation (RAF) followed by degradation. The results indicated the lowest energy for addition of the first NO(•) at C7 with an activation free energy of ?G(?) = 74.40 kJ mol(-1) and a rate constant of 0.56 s(-1), followed by trans-addition of a second NO(•) at C8 with ?G(?) = 55.51 kJ mol(-1). MS confirmed the formation of a dinitrosyl-?-Car (596.6 m/z), and of a ?-Car fragment (400.4 m/z) formed by C7/C8 bond cleavage and suggested to be of importance for progression of bleaching. Up to eight reaction products with increasing mass of 28 m/z are assigned to continuous addition of NO(•) to the initially formed fragment forming nitroxides. Continuous wave photolysis of sodium nitroprusside (SNP) as a NO(•) source dissolved together with ?-Car in 4:1 (v/v) methanol:tetrahydrofuran gradually bleached ?-Car. Nanosecond laser flash photolysis at 355 nm followed by transient absorption spectroscopy showed a ?-Car derived intermediate with an absorption maximum around 420 nm in agreement with a prediction (425 nm) from time-dependent DFT (TDDFT) for the trans-C7,8 dinitrosyl adduct of ?-Car. The NO(•) adduct of ?-Car decays with a rate constant of ?10(7) s(-1) at 25 °C.
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Changes in brain functional network connectivity after stroke.
Neural Regen Res
PUBLISHED: 09-11-2014
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Studies have shown that functional network connection models can be used to study brain network changes in patients with schizophrenia. In this study, we inferred that these models could also be used to explore functional network connectivity changes in stroke patients. We used independent component analysis to find the motor areas of stroke patients, which is a novel way to determine these areas. In this study, we collected functional magnetic resonance imaging datasets from healthy controls and right-handed stroke patients following their first ever stroke. Using independent component analysis, six spatially independent components highly correlated to the experimental paradigm were extracted. Then, the functional network connectivity of both patients and controls was established to observe the differences between them. The results showed that there were 11 connections in the model in the stroke patients, while there were only four connections in the healthy controls. Further analysis found that some damaged connections may be compensated for by new indirect connections or circuits produced after stroke. These connections may have a direct correlation with the degree of stroke rehabilitation. Our findings suggest that functional network connectivity in stroke patients is more complex than that in hea-lthy controls, and that there is a compensation loop in the functional network following stroke. This implies that functional network reorganization plays a very important role in the process of rehabilitation after stroke.
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A novel synthetic route towards monodisperse ?-NaYF4:Ln(3+) micro/nanocrystals from layered rare-earth hydroxides at ultra low temperature.
Chem. Commun. (Camb.)
PUBLISHED: 09-11-2014
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Monodisperse ?-NaYF4:Ln(3+) (Ln = Yb/Er, Yb/Tm) single micro/nanocrystals were first one-pot fabricated at 50 °C through a novel synthetic route containing two pivotal processes: (a) synthesis of a ?-NaYF4 {0001} unit layer through a novel style of ion-exchange from Y2(OH)5NO3·nH2O (LYH) and (b) the subsequent oriented-assembly process.
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Association of the HLA-DRB1 with scleroderma in Chinese population.
PLoS ONE
PUBLISHED: 09-03-2014
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Multiple alleles of the Human leukocyte antigen (HLA) DRB1 have been strongly associated with systemic sclerosis (SSc) and its clinical or serological subsets. However, the associations vary in different ethnic populations. To define SSc-risk and/or -protective alleles of HLA-DRB1 in Chinese population, we studied a Han Chinese cohort containing 585 patients with SSc and 458 gender-matched, unrelated controls. The HLA-DRB1 genotyping was performed with sequence-based typing method. Exact p-values were obtained (Fisher's test) from 2×2 tables of allele frequency and disease status. The major SSc-risk allele subtypes of HLA-DRB1 are the DRB1*15?02 and *16?02 in this Chinese cohort. Particularly, DRB1*15?02 was most significantly associated with anti-centromere autoantibodies (ACA) positive, and DRB1*16?02 with anti-topoisomerase I autoantibodies (ATA) positive patients. On the other hand, DRB1*01?01 and *04?06 were strong SSc-protective alleles in Chinese, especially in patients who were ACA positive and had diffuse cutaneous SSc (dcSSc), respectively. In addition, DRB1*11 and *07?01 also showed significant association with SSc as a risk for and protection from SSc, respectively, and which is consistent with the studies of Spanish, US Caucasian and Hispanic populations. DRB1*15 was associated with ATA positive Chinese SSc that is consistent with Black South African and Korean SSc. These findings of HLA-DRB1 alleles in association with Chinese SSc provide the growing knowledge of genetics of SSc, and indicate that the genetic heterogeneity among ethnicities may significantly impact the complex trait of SSc.
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Metabolism in HD: still a relevant mechanism?
Mov. Disord.
PUBLISHED: 08-13-2014
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The polyglutamine expansion within huntingtin is the causative factor in the pathogenesis of Huntington's disease (HD). Although the underlying mechanisms by which mutant huntingtin causes neuronal dysfunction and degeneration have not been fully elucidated, compelling evidence suggests that mitochondrial dysfunction and compromised energy metabolism are key players in HD pathogenesis. Longitudinal studies of HD subjects have shown reductions in glucose utilization before the disease clinical onset. Preferential striatal neurodegeneration, a hallmark of HD pathogenesis, also has been associated with interrupted energy metabolism. Data from genetic HD models indicate that mutant huntingtin disrupts mitochondrial bioenergetics and prevents adenosine triphosphate (ATP) generation, implying altered energy metabolism as an important component of HD pathogenesis. Here we revisit the evidence of abnormal energy metabolism in the central nervous system of HD patients, review our current understanding of the molecular mechanisms underlying abnormal metabolism induced by mutant huntingtin, and discuss the promising therapeutic development by halting abnormal metabolism in HD.
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Intracellular antioxidant detoxifying effects of diosmetin on 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative stress through inhibition of reactive oxygen species generation.
J. Agric. Food Chem.
PUBLISHED: 08-13-2014
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The intracellular antioxidant activities of diosmetin were evaluated by cellular antioxidant activity (CAA) assay, 2,2-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced erythrocyte hemolysis assay and cupric chloride (CuCl2)-induced plasma oxidation assay. The results showed that diosmetin exhibits strong cellular antioxidant activity (EC50 = 7.98 ?mol, CAA value = 58 ?mol QE/100 ?mol). It was also found that diosmetin treatment could effectively attenuate AAPH-induced erythrocyte hemolysis (91.0% inhibition at 100 ?g/mL) and CuCl2-induced plasma oxidation through inhibition of intracellular reactive oxygen species (ROS) generation. Diosmetin could significantly restore AAPH-induced increase of intracelluar antioxidant enzyme (SOD, GPx, and CAT) activities to normal levels, as well as inhibit intracellular malondialdehyde (MDA) formation. Thus, the intracellular antioxidant detoxifying mechanism of diosmetin is associated with both nonenzymatic and enzymatic defense systems.
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Retinal ischemia/reperfusion injury is mediated by Toll-like receptor 4 activation of NLRP3 inflammasomes.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 08-07-2014
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Retinal ischemia/reperfusion (IR) is common in eye disorders. Pattern-recognition receptors (PRRs) are reported to initiate sterile inflammatory response. The role of PRRs in retinal IR injury is currently unknown. Thus, we investigated the expression and function of membrane and cytoplasmic PRRs during retinal IR.
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Ultrathin and lightweight 3D free-standing Ni@NiO nanowire membrane electrode for a supercapacitor with excellent capacitance retention at high rates.
ACS Appl Mater Interfaces
PUBLISHED: 08-07-2014
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A free-standing binder-free 3D Ni@NiO nanowire membrane is fabricated by a simple filtration method followed by thermal annealing. With an appropriate annealing temperature, the functional nanowires can keep their rough and echinate surface, and the conductive network composed of welded nickel nanowire cores is well-preserved without isolation (0.53 ?/sq). The unique 3D multigrade mesporous structure not only accelerates the intercalation and deintercalation velocity of electrolyte ions but also provides numerous electroactive sites for the Faraday reaction. As a result, the supercapacitor electrode can preserve a capacitance retention of 96.1% (36.9 F/cm(3)) with a high discharge current density, indicating its wonderful rate capability. The fabricated membrane electrode exhibits high volumetric capacitance, stable cycling life, and remarkable retention of the capacitance at high rate, energy, and power density, making it a promising candidate for application in portable electronic products.
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The Mediterranean Diet and Gastrointestinal Cancers Risk.
Recent Pat Food Nutr Agric
PUBLISHED: 07-29-2014
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It is known that Mediterranean diet (MD), which is characterized by high consumption of vegetables, fruits, cereals, beans, nuts, and olive oil, moderate consumption of fish, white meat, eggs, dairy products, and alcohol, and low consumption of red meat, processed meats, and foods rich in sugars or fats, can reduce the risk of cardiovascular diseases, type 2 diabetes, neurodegenerative diseases and cancers. Previous epidemiologic studies had confirmed the protective role in the incidence and mortality of gastrointestinal cancers. This review discusses the Mediterranean dietary and gastrointestinal cancers risk through the studies which examined esophageal cancer, gastric cancer, pancreatic cancer, or colorectal cancer. According to the studies, MD associated with a significant reduction in the risk of gastrointestinal cancers. But there is a lack of definitive evidences for the association between MD and adjunctive therapy for gastrointestinal cancers. Considering the complexity of tumor etiology, we propose that design more related researches and more comprehensive data, which include diet, exercise and psychological integrated researches to reveal the relationship between MD and cancer.
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Facile fabrication of single-phase multifunctional BaGdF5 nanospheres as drug carriers.
ACS Appl Mater Interfaces
PUBLISHED: 07-10-2014
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Multifunctional BaGdF5 nanospheres with mesoporous, luminescent, and magnetic properties have been successfully synthesized with the assistance of trisodium citrate by a hydrothermal method. The mesoporous structure is revealed by scanning electron microscope and transmission electron microscope images as well as N2 adsorption-desorption isotherm. The as-synthesized BaGdF5 nanospheres exhibit an intense broad bluish emission (centered at 450 nm) under the excitation of 390 nm, which might originate from the CO2·(-) radical-related defect produced by Cit(3-) groups. It is also shown that these BaGdF5 nanospheres brightened the T1-weighted images, suggesting that they could act as T1 contrast agents for magnetic resonance imaging. Using metformin hydrochloride as the model drug, the luminescent porous spheres show good drug storage/release capability. Furthermore, the emission intensity varies as a function of the cumulative drug release, making the drug-carrying system easily trackable and monitorable by detecting the luminescence intensity. Additionally, the paramagnetic property, originating from the unpaired electrons of Gd(3+) ions, opens the possibility of directing the magnetic targeted carrier to the pathological site by magnetic field gradient.
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Hypothetical Link between Infertility and Genetically Modified Food.
Recent Pat Food Nutr Agric
PUBLISHED: 07-05-2014
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It is speculated that genetically modified food (GMF)/genetically modified organism (GMO) is responsible for infertility development. The risk associated with a wide use of GMFs/GMOs provides the basis for social criticism. However, to date, it has not been clarified whether the harmful effects is directly resulted from products of genetic modifications or from the transgenesis process. Extensive experience with the risk assessment of whole foods has been applied recently on the safety and nutritional testing of GMFs/GMOs. Investigations including sub-acute, chronic, reproductive, multi-generation and carcinogenicity studies have tested the safety of GMFs. We extrapolated the potential risks associated with GMFs/GMOs on reproduction, and analyzed the multi-aspect linked between infertility and GMFs/GMOs. It could be conjectured that GMFs/GMOs could exist potential hazard on reproduction, linking to the development of infertility through influencing the endocrine metabolism, endometriosis. However, little evidence shows the impaction on embryo or reproductive related tumor due to the limited literatures, and needs further research. The article presents some related patents on GMFs/GMOs, and some methods for tracking GMOs.
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Dissection of the mechanism of traditional Chinese medical prescription-Yiqihuoxue formula as an effective anti-fibrotic treatment for systemic sclerosis.
BMC Complement Altern Med
PUBLISHED: 06-30-2014
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Systemic sclerosis (SSc) is a connective tissue fibrotic disease for which there is no effective treatment. Traditional Chinese Medicine (TCM), such as the Yiqihuoxue formula used in Shanghai TCM-integrated Hospital, has shown the efficacy of anti-fibrosis in clinical applications. This study was aiming to dissect the anti-fibrotic mechanism of Yiqihuoxue treatment for SSc.
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Electrocatalytic oxygen evolution over supported small amorphous Ni-Fe nanoparticles in alkaline electrolyte.
Langmuir
PUBLISHED: 06-24-2014
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The electrocatalytic oxygen evolution reaction (OER) is a critical anode reaction often coupled with electron or photoelectron CO2 reduction and H2 evolution reactions at the cathode for renewable energy conversion and storage. However, the sluggish OER kinetics and the utilization of precious metal catalysts are key obstacles in the broad deployment of these energy technologies. Herein, inexpensive supported 4 nm Ni-Fe nanoparticles (NiyFe1-yOx/C) featuring amorphous structures have been prepared via a solution-phase nanocapsule method for active and durable OER electrocatalysts in alkaline electrolyte. The Ni-Fe nanoparticle catalyst containing 31% Fe (Ni0.69Fe0.31Ox/C) shows the highest activity, exhibiting a 280 mV overpotential at 10 mA cm(-2) (equivalent to 10% efficiency of solar-to-fuel conversion) and a Tafel slope of 30 mV dec(-1) in 1.0 M KOH solution. The achieved OER activity outperforms NiOx/C and commercial Ir/C catalysts and is close to the highest performance of crystalline Ni-Fe thin films reported in the literature. In addition, a Faradaic efficiency of 97% measured on Ni0.69Fe0.31Ox/C suggests that carbon support corrosion and further oxidation of nanoparticle catalysts are negligible during the electrocatalytic OER tests. Ni0.69Fe0.31Ox/C further demonstrates high stability as there is no apparent OER activity loss (based on a chronoamperometry test) or particle aggregation (based on TEM image observation) after a 6 h anodization test. The high efficiency and durability make these supported amorphous Ni-Fe nanoparticles potentially applicable in the (photo)electrochemical cells for water splitting to make H2 fuel or CO2 reduction to produce usable fuels and chemicals.
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Effects of p75 neurotrophin receptor on regulating hypoxia-induced angiogenic factors in retinal pigment epithelial cells.
Mol. Cell. Biochem.
PUBLISHED: 06-22-2014
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Retinal pigment epithelium (RPE) exerts critical roles in the maintenance of the normal functions of the retina, whereas RPE dysfunction can induce retina neovascularization. p75 neurotrophin receptor (p75(NTR)) has been shown to play essential roles in angiogenesis. However, the function of p75(NTR) in the RPE remains unclear. In the present study, we demonstrated that p75(NTR) was highly expressed in the human choroidal neovascularization membranes. For in vitro study, RPE was exposed to hypoxia, and a knockdown of p75(NTR) was achieved via lentivirus-mediated RNA interference. The results showed that hypoxia induced the expression of p75(NTR) in the RPE, and the knockdown of p75(NTR) rescued RPE proliferation activity and inhibited apoptosis which induced by hypoxia. After the deletion of p75(NTR), RPE-secreted pro-angiogenic factors (vascular endothelial growth factor and platelet-derived growth factor), inflammatory factors [interleukin 1 beta (IL1?), IL18, and stromal cell-derived factor 1], and matrix metalloproteinases (MMPs) (MMP3 and MMP9) were down-regulated under hypoxic conditions. While the RPE secreted anti-angiogenic factors (pigment epithelium-derived factor) and angiostatin, the tissue inhibitors of metalloproteinases (TIMPs) (TIMP-1 and TIMP-3) were up-regulated after the knockdown of p75(NTR). The human umbilical vein endothelial tube formation ability can be inhibited when it is co-cultured with the supernatant extract from p75(NTR)-knockdown RPE under hypoxic induction. These results suggest that the knockdown of p75(NTR) suppressed pro-angiogenic factors which induced by hypoxia while promoting the anti-angiogenesis-related factors in the RPE. It is indicated that p75(NTR) could be a potential therapeutic target for RPE hypoxia or oxidative stress diseases.
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Enolase of Angiostrongylus cantonensis: more likely a structural component?
Parasitol. Res.
PUBLISHED: 06-12-2014
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The cloned enolase gene of Angiostrongylus cantonensis (AcEno) comprised 1,667 bp and encoded a peptide with 434 amino acid residues which lacked of a signal peptide but contained a transmembrane region, indicating that AcEno tends to be a structural component (intracellular or membrane protein). The real-time PCR revealed a meaningful difference in the expression level of AcEno in varied development stages. By immunolocalization, native AcEno was detected mainly in the cytoplasm in most tissues, such as parietal muscle, genital tracts, nerve ring, and alimentary canal where the energy consumption is high, but not as expected on the cuticle and hypodermis layer of the nematode. This suggests that the AcEno may be involved in a host of other biological functions, rather than a receptor of plasminogen or a component of excretory-secretory antigen. In addition, AcEno expressed alike in the nucleus, indicating that AcEno also involved in regulating the continuous growth and development of A. cantonensis in hosts. Despite of living in the vasculature at a certain stage of life cycle, AcEno was not localized in the outer surface of L3 and adults, indicating that A. cantonensis may have other virulence and immune evasion mechanisms.
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[Study on the accurate effects of radial shock wave therapy equipment].
Zhongguo Yi Liao Qi Xie Za Zhi
PUBLISHED: 05-21-2014
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The basic mechanical properties of a Radial Shock Wave Therapy Equipment (RSWTE) were experimentally studied in this paper. The output energy of the RSWTE working on the operation frequency of 10 Hz was measured by dynamic pressure transducer under the conditions of different operation pressure. The results showed that both operation pressure and operation frequency have effects on the output energy of the equipment. The output energy increases with the increase of operation pressure, and the magnitude of increased energy decreases with higher operation of frequency. With the increase of operation frequency, the output energy rises up in condition of lower operation pressure and drops off in condition of higher operation pressure. The accurate medical treatment should be selected with the optimized energy and condition according to the treatment requirement to different illness in clinical medical applications.
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Recrystallization of Dihydromyricetin from Ampelopsis grossedentata and Its Anti-Oxidant Activity Evaluation.
Rejuvenation Res
PUBLISHED: 05-20-2014
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Abstract A fast and efficient method for purification of dihydromyricetin (3,5,7,3',4',5'-six hydroxy-2,3-dihydro flavonol; DMY) from Ampelopsis grossedentata was created by crystallization eight times at 25°C, and a purity of 98% was finally achieved. The purified DMY exhibited high oxygen radical absorbance capacity (ORAC) (30.21 ?mol Trolox equiv/mg) and strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (half-maximal inhibitory concentration [IC50]=0.235 ?g/mL). The addition of DMY could also effectively attenuate 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced human erythrocyte hemolysis and cupric chloride (CuCl2)-induced human plasma lipid peroxidation via inhibition of intracellular reactive oxygen species (ROS) generation. It was also found that DMY (>12 ?g/mL) treatment significantly inhibited intracellular malondialdehyde (MDA) formation. Meanwhile, DMY treatment significantly inhibited the obvious increase of anti-oxidant enzymes levels (superoxide dismutase [SOD]; glutathione peroxidase [GPX], and catalase [CAT]) induced by AAPH radicals, suggesting that stress defense mechanisms are associated with protection of DMY against intracellular oxidation.
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Immunolocalization and developmental expression patterns of two cathepsin B proteases (AC-cathB-1, -2) of Angiostrongylus cantonensis.
Exp. Parasitol.
PUBLISHED: 04-28-2014
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In this study we have investigated the anatomic sites of expression and developmental expression patterns of two cathepsin B-like cysteine proteases (AC-cathB-1, -2) of Angiostrongylus cantonensis. The immunolocalization results revealed that native AC-cathBs were found present in the L1 and L3 larvae, female and male adults, and the AC-cathBs were localized mainly on the digestive tract of A. cantonensis and expressed at varied levels and in different patterns in the internal tissues according to their developmental stage. Consistent with the infective stage of L3 is a much more intense staining of AC-cathBs in the esophagus compared with the intestine. In contrast to L3, more abundant signals were located to the intestine of adults, suggesting that nutrition digestion likely to be the main function of the protease at this point. AC-cathBs fluorescent signals were present in excretory pore, excretory tube in lateral cords, and muscular esophagus of larvae, further supported the AC-cathB-1, -2 likely to be released by A. cantonensis as excretory/secretory products. Additionally, only the protein AC-cathB-2 was detected in the reproductive system, especially in the wall of vas deferens, uterus, and oviduct of the parasites, whether the AC-cathB-2 has some function in germ cells development and maturation need to be further characterized. Although the anatomic sites and expression patterns were different in larvae and adults and the corresponding function might not the same, AC-cathB-1 and -2 involved in the host-parasite interaction in addition to digestive function.
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Realizing full visible spectrum metamaterial half-wave plates with patterned metal nanoarray/insulator/metal film structure.
Opt Express
PUBLISHED: 04-11-2014
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Abrupt phase shift introduced by plasmonic resonances has been frequently used to design subwavelength wave plates for optical integration. Here, with the sandwich structure consisting of a top periodic patterned silver nanopatch, an in-between insulator layer and a bottom thick Au film, we realize a broadband half-wave plate which is capable to cover entire visible light spectrum ranging from 400 to 780 nm. Moreover, when the top layer is replaced with a periodic array of composite super unit cell comprised of two nanopatches with different sizes, the operation bandwidth can be further improved to exceed an octave (400-830 nm). In particular, we demonstrate that the designed half-wave plate can be used efficiently to rotate the polarization state of an ultra-fast light pulse with reserved pulse width. Our result offers a new strategy to design and construct broadband high efficiency phase-response based optical components using patterned metal nanoarray/insulator/metal structure.
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A tutorial for understanding chemical reactivity through the valence bond approach.
Chem Soc Rev
PUBLISHED: 04-08-2014
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This is a tutorial on the usage of valence bond (VB) diagrams for understanding chemical reactivity in general, and hydrogen atom transfer (HAT) reactivity in particular. The tutorial instructs the reader how to construct the VB diagrams and how to estimate HAT barriers from raw data, starting with the simplest reaction H + H2 and going all the way to HAT in the enzyme cytochrome P450. Other reactions are treated as well, and some unifying principles are outlined. The tutorial projects the unity of reactivity treatments, following Coulson's dictum "give me insight, not numbers", albeit with its modern twist: giving numbers and insight.
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A prospective study of arm circumference and risk of death in Bangladesh.
Int J Epidemiol
PUBLISHED: 04-07-2014
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Epidemiological studies have observed protective effects of mid-upper arm circumference (MUAC) against all-cause mortality mostly in Western populations. However, evidence on cause-specific mortality is limited.
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Different hereditary contribution of the CFH gene between polypoidal choroidal vasculopathy and age-related macular degeneration in Chinese Han people.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 04-03-2014
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To investigate whether 11 variants in complement factor H gene contributed differently in patients with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) of Chinese descent.
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Long-term outcome of IgA nephropathy patients with recurrent macroscopic hematuria.
Am. J. Nephrol.
PUBLISHED: 02-27-2014
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The long-term renal outcomes of patients with IgA nephropathy (IgAN) who present with recurrent macroscopic hematuria (RMH) have not been described in previous studies.
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The complete mitochondrial genomes of sixteen ardeid birds revealing the evolutionary process of the gene rearrangements.
BMC Genomics
PUBLISHED: 02-09-2014
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The animal mitochondrial genome is generally considered to be under selection for both compactness and gene order conservation. As more mitochondrial genomes are sequenced, mitochondrial duplications and gene rearrangements have been frequently identified among diverse animal groups. Although several mechanisms of gene rearrangement have been proposed thus far, more observational evidence from major taxa is needed to validate specific mechanisms. In the current study, the complete mitochondrial DNA of sixteen bird species from the family Ardeidae was sequenced and the evolution of mitochondrial gene rearrangements was investigated. The mitochondrial genomes were then used to review the phylogenies of these ardeid birds.
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Reaction mechanism of homoprotocatechuate 2,3-dioxygenase with 4-nitrocatechol: implications for the role of substrate.
J Phys Chem B
PUBLISHED: 02-05-2014
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The reaction mechanism of the dioxygen activation by homoprotocatechuate 2,3-dioxygenase (HPCD) with the substrate 4-nitrocatechol was investigated by quantum mechanical/molecular mechanical calculations. Our results demonstrated that the experimentally determined side-on iron-oxygen complex in crystallo is a semiquinone substrate radical (SQ(•))-Fe(III)-hydroperoxo species, which could not act as the reactive species. In fact, the Fe(III)-superoxo species with a hydrogen bond between His200 and the proximal oxygen is the reactive oxygen species. The second-sphere His200 residue was found to play an important role in manipulating the orientation of the superoxide in the Fe-O2 adduct for the further reaction. The rate-limiting step is the attack of the superoxo group on the substrate with a barrier of 17.2 kcal/mol, in good agreement with the experimental value of 16.8 kcal/mol. The reaction mechanism was then compared with the one for HPCD with its native substrate homoprotocatechuate studied recently by the same methods, in which a hybrid SQ(•)-Fe(II)-O2(•-)/Fe(III)-O2(•-) was suggested to be the reactive species. Therefore, our studies suggested that the substrate plays important roles in the dioxygen activation by HPCD.
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Design of a luminescence pattern via altering the crystal structure and doping ions to create warm white LEDs.
Chem. Commun. (Camb.)
PUBLISHED: 01-29-2014
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Presently considerable interest in phosphor-converted warm LEDs which meet the stringent requirements of general illumination is stimulated. Here we report warm white LEDs made by altering the crystal structure and doping ions, which can govern the luminescence pattern to modulate the correlated color temperature and color-rendering index.
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Discriminative analysis of multivariate features from structural MRI and diffusion tensor images.
Magn Reson Imaging
PUBLISHED: 01-23-2014
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Imaging markers derived from magnetic resonance images, together with machine learning techniques allow for the recognition of unique anatomical patterns and further differentiating Alzheimer's disease (AD) from normal states. T1-based imaging markers, especially volumetric patterns have demonstrated their discriminative potential, however, rely on the tissue abnormalities of gray matter alone. White matter abnormalities and their contribution to AD discrimination have been studied by measuring voxel-based intensities in diffusion tensor images (DTI); however, no systematic study has been done on the discriminative power of either region-of-interest (ROI)-based features from DTI or the combined features extracted from both T1 images and DTI. ROI-based analysis could potentially reduce the feature dimensionality of DTI indices, usually from more than 10e+5, to 10-150 which is almost equal to the order of magnitude with respect to volumetric features from T1. Therefore it allows for straight forward combination of intensity based landmarks of DTI indices and volumetric features of T1. In the present study, the feasibility of tract-based features related to Alzheimer's disease was first evaluated by measuring its discriminative capability using support vector machine on fractional anisotropy (FA) maps collected from 21 subjects with Alzheimer's disease and 15 normal controls. Then the performance of the tract-based FA+gray matter volumes-combined feature was evaluated by cross-validation. The combined feature yielded good classification result with 94.3% accuracy, 95.0% sensitivity, 93.3% specificity, and 0.96 area under the receiver operating characteristic curve. The tract-based FA and the tract-based FA+gray matter volumes-combined features are certified their feasibilities for the recognition of anatomical features and may serve to complement classification methods based on other imaging markers.
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Maximizing integrated optical and electrical properties of a single ZnO nanowire through native interfacial doping.
Adv. Mater. Weinheim
PUBLISHED: 01-22-2014
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A native interfacial doping layer introduced in core-shell type ZnO nano-wires by a simple vapor phase re-growth procedure endows the produced nano-wires with both excellent electrical and optical performances compared to conventional homogeneous ZnO nanowires. The unique Zn-rich interfacial structure in the core-shell nanowires plays a crucial role in the outstanding performances.
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Association between arsenic exposure from drinking water and hematuria: results from the Health Effects of Arsenic Longitudinal Study.
Toxicol. Appl. Pharmacol.
PUBLISHED: 01-18-2014
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Arsenic (As) exposure has been associated with both urologic malignancy and renal dysfunction; however, its association with hematuria is unknown. We evaluated the association between drinking water As exposure and hematuria in 7843 men enrolled in the Health Effects of Arsenic Longitudinal Study (HEALS). Cross-sectional analysis of baseline data was conducted with As exposure assessed in both well water and urinary As measurements, while hematuria was measured using urine dipstick. Prospective analyses with Cox proportional regression models were based on urinary As and dipstick measurements obtained biannually since baseline up to six years. At baseline, urinary As was significantly related to prevalence of hematuria (P-trend<0.01), with increasing quintiles of exposure corresponding with respective prevalence odds ratios of 1.00 (reference), 1.29 (95% CI: 1.04-1.59), 1.41 (95% CI: 1.15-1.74), 1.46 (95% CI: 1.19-1.79), and 1.56 (95% CI: 1.27-1.91). Compared to those with relatively little absolute urinary As change during follow-up (-10.40 to 41.17 ?g/l), hazard ratios for hematuria were 0.99 (95% CI: 0.80-1.22) and 0.80 (95% CI: 0.65-0.99) for those whose urinary As decreased by >47.49 ?g/l and 10.87 to 47.49 ?g/l since last visit, respectively, and 1.17 (95% CI: 0.94-1.45) and 1.36 (95% CI: 1.10-1.66) for those with between-visit increases of 10.40 to 41.17 ?g/l and >41.17 ?g/l, respectively. These data indicate a positive association of As exposure with both prevalence and incidence of dipstick hematuria. This exposure effect appears modifiable by relatively short-term changes in drinking water As.
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Association between anthropometric measures of obesity and subclinical atherosclerosis in Bangladesh.
Atherosclerosis
PUBLISHED: 01-10-2014
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Anthropometric measures such as waist-hip-ratio (WHR), waist-height-ratio (WHtR), waist circumference, Mid-upper arm circumference (MUAC), and upper thigh circumference, have been linked to the risk of cardiovascular disease (CVD). However, their relationships with subclinical atherosclerosis are unclear. Studies in normal-weight populations, especially in Asian countries where leanness is prevalent, are lacking.
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rs4711751 and rs1999930 are not associated with neovascular age-related macular degeneration or polypoidal choroidal vasculopathy in the Chinese population.
Ophthalmic Res.
PUBLISHED: 01-08-2014
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rs1999930 and rs4711751 have recently been identified as novel variants associated with advanced age-related macular degeneration (AMD) in populations of European ancestry. We aimed to investigate whether these two single nucleotide polymorphisms (SNPs) were associated with neovascular AMD (nAMD) or with polypoidal choroidal vasculopathy (PCV), a variant of AMD in Asians, using a Chinese case-control study.
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Study of bilineage differentiation of human-bone-marrow-derived mesenchymal stem cells in oxidized sodium alginate/N-succinyl chitosan hydrogels and synergistic effects of RGD modification and low-intensity pulsed ultrasound.
Acta Biomater
PUBLISHED: 01-03-2014
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The level of formation of new bone and vascularization in bone tissue engineering scaffold implants is considered as a critical factor for clinical application. In this study, an approach using an RGD-grafted oxidized sodium alginate/N-succinyl chitosan (RGD-OSA/NSC) hydrogel as a scaffold and low-intensity pulsed ultrasound (LIPUS) as mechanical stimulation was proposed to achieve a high level of formation of new bone and vascularization. An in vitro study of endothelial and osteogenic differentiations of human-bone-marrow-derived mesenchymal stem cells (hMSCs) was conducted to evaluate it. The results showed that RGD-OSA/NSC composite hydrogels presented good biological properties in attachment, proliferation and differentiation of cells. The MTT cell viability assay showed that the total number of cells increased more significantly in the LIPUS-stimulated groups with RGD than that in the control ones; similar results were obtained for alkaline phosphatase activity/staining and mineralized nodule formation assay of osteogenic induction and immunohistochemical test of endothelial induction. The positive synergistic effect of LIPUS and RGD on the enhancement of proliferation and differentiation of hMSCs was observed. These findings suggest that the hybrid use of RGD modification and LIPUS might provide one approach to achieve a high level of formation of new bone and vascularization in bone tissue engineering scaffold implants.
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Transferrin-targeted magnetic/fluorescence micelles as a specific bi-functional nanoprobe for imaging liver tumor.
Nanoscale Res Lett
PUBLISHED: 01-01-2014
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In order to delineate the location of the tumor both before and during operation, we developed targeted bi-functional polymeric micelles for magnetic resonance (MR) and fluorescence imaging in liver tumors. Hydrophobic superparamagnetic iron oxide nanoparticles (SPIONs) were loaded into the polymeric micelles through self-assembly of an amphiphilic block copolymer poly(ethylene glycol)-poly(?-caprolactone). After, transferrin (Tf) and near-infrared fluorescence molecule Cy5.5 were conjugated onto the surface of the polymeric micelles to obtain the nanosized probe SPIO@PEG-b-PCL-Tf/Cy5.5 (SPPTC). Imaging capabilities of this nanoprobe were evaluated both in vitro and in vivo. The accumulation of SPPTC in HepG2 cells increased over SPIO@PEG-b-PCL-Cy5.5 (SPPC) by confocal microscopy. The targeted nanoprobe SPPTC possessed favorable properties on the MR and fluorescence imaging both in vitro and in vivo. The MTT results showed that the nanoprobes were well tolerated. SPPTC had the potential for pre-operation evaluation and intra-operation navigation of tumors in clinic.
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Semaphorin 3A blocks the formation of pathologic choroidal neovascularization induced by transforming growth factor beta.
Mol. Vis.
PUBLISHED: 01-01-2014
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Choroidal neovascularization (CNV) is a major cause of vision loss in retinal diseases such as age-related macular degeneration (AMD). Previously, we demonstrated that semaphorin3A (Sema3A), which is a chemorepellent guidance molecule, inhibited the formation of retina neovascularization. In the present study, we investigated the antiangiogenic effects of Sema3A on transforming growth factor beta (TGF-?) in vitro and in vivo.
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Genotypes and Transmitted Drug Resistance among Treatment-Naive HIV-1-Infected Patients in a Northwestern Province, China: Trends from 2003 to 2013.
PLoS ONE
PUBLISHED: 01-01-2014
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Transmitted drug resistance (TDR) reduces the efficacy of initial antiretroviral treatment and has become a public health concern. Little information is available regarding the genetic diversity of HIV-1 and the prevalence of TDR among treatment-naïve patients in a northwestern province of China since the implementation of national free antiretroviral therapy (ART).
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Lack of Association of the CD247 SNP rs2056626 with Systemic Sclerosis in Han Chinese.
Open Rheumatol J
PUBLISHED: 01-01-2014
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Systemic sclerosis (SSc) is a complex disease involving multiple genetic factors. A recent genome-wide association study (GWAS) indicated that CD247 was strongly associated with SSc, which was subsequently confirmed in a SSc cohort of European population. However, genetic heterogeneity in different ethnic populations may significantly impact the complex trait of SSc. The studies herein aimed to examine whether the SSc-associated SNP rs2056626 of CD247 identified in Caucasian is also associated with Han Chinese SSc. A Han Chinese cohort consisting of 387 SSc patients and 523 healthy controls were examined in the studies. TaqMan assays were performed to examine the SNP. Exact p-values were obtained (Fisher's test) from 2x2 tables of allele counts and disease status. The results showed that there was no association between rs2056626 of CD247 and SSc or any SSc subtypes of Han Chinese. The negative results are important in understanding genetics of SSc in different ethnic populations, which further suggest complex nature of genetics of SSc.
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Relationship of the changes of cervical MRI, TCD and BAEP in patients with "isolated" vertigo.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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To study the relationship and changes of cervical MRI, TCD and BAEP in patients with "isolated" vertigo.
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Comparative analysis of arterial spin labeling and dynamic susceptibility contrast perfusion imaging for quantitative perfusion measurements of brain tumors.
Int J Clin Exp Pathol
PUBLISHED: 01-01-2014
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We comparatively analyzed the difference between three-dimensional arterial spin labeling (3D-ASL) and the conventional dynamic susceptibility contrast (DSC) perfusion imaging in the setting of assessing brain tumor perfusion in 28 patients with proved brain tumors. All patients were scheduled with standard MRI, 3D-ASL and DSC scannings on a GE DISCOVERY MR 750 system. Maximal relative tumor perfusion was obtained based on the region of interest (ROI) method. A close correlation between 3D-ASL and DSC perfusion imaging was noted as manifested by the absence of significant differences between ASL nTBF and DSC nTBF when normalized to M (mirror region) and GM (contralateral gray matter). However, ASL nTBF was found to be highly correlated with DSC nTBF and DSC nTBV when normalized to M, GM and WM (contralateral normal white matter). Together, our data support that 3D-ASL possesses the potential to be a noninvasive alternate for DSC-MRI in assessing brain tumor perfusion in the setting of treatment prognosis and metastasis, particularly for those patients with renal failure and patients required for collection of follow up information.
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A novel humanized GLP-1 receptor model enables both affinity purification and Cre-LoxP deletion of the receptor.
PLoS ONE
PUBLISHED: 01-01-2014
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Class B G protein-coupled receptors (GPCRs) are important regulators of endocrine physiology, and peptide-based therapeutics targeting some of these receptors have proven effective at treating disorders such as hypercalcemia, osteoporosis, and type 2 diabetes mellitus (T2DM). As next generation efforts attempt to develop novel non-peptide, orally available molecules for these GPCRs, new animal models expressing human receptor orthologs may be required because small molecule ligands make fewer receptor contacts, and thus, the impact of amino acid differences across species may be substantially greater. The objective of this report was to generate and characterize a new mouse model of the human glucagon-like peptide-1 receptor (hGLP-1R), a class B GPCR for which established peptide therapeutics exist for the treatment of T2DM. hGLP-1R knock-in mice express the receptor from the murine Glp-1r locus. Glucose tolerance tests and gastric emptying studies show hGLP-1R mice and their wild-type littermates display similar physiological responses for glucose metabolism, insulin secretion, and gastric transit, and treatment with the GLP-1R agonist, exendin-4, elicits similar responses in both groups. Further, ex vivo assays show insulin secretion from humanized islets is glucose-dependent and enhanced by GLP-1R agonists. To enable additional utility, the targeting construct of the knock-in line was engineered to contain both flanking LoxP sites and a C-terminal FLAG epitope. Anti-FLAG affinity purification shows strong expression of hGLP-1R in islets, lung, and stomach. We crossed the hGLP-1R line with Rosa26Cre mice and generated global Glp-1r-/- animals. Immunohistochemistry of pancreas from humanized and knock-out mice identified a human GLP-1R-specific antibody that detects the GLP-1R in human pancreas as well as in the pancreas of hGLP-1r knock-in mice. This new hGLP-1R model will allow tissue-specific deletion of the GLP-1R, purification of potential GLP-1R partner proteins, and testing of novel therapeutic agents targeting the hGLP-1R.
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Temporal profile of the renal transcriptome of HIV-1 transgenic mice during disease progression.
PLoS ONE
PUBLISHED: 01-01-2014
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Profiling of temporal changes of gene expression in the same kidney over the course of renal disease progression is challenging because repeat renal biopsies are rarely indicated in clinical practice. Here, we profiled the temporal change in renal transcriptome of HIV-1 transgenic mice (Tg26), an animal model for human HIV-associated nephropathy (HIVAN), and their littermates at three different time points (4, 8, and 12 weeks of age) representing early, middle, and late stages of renal disease by serial kidney biopsy. We analyzed both static levels of gene expression at three stages of disease and dynamic changes in gene expression between different stages. Analysis of static and dynamic changes in gene expression revealed that up-regulated genes at the early and middle stages are mostly involved in immune response and inflammation, whereas down-regulated genes mostly related to fatty acid and retinoid metabolisms. We validated the expression of a selected panel of genes that are up-regulated at the early stage (CCL2, CCL5, CXCL11, Ubd, Anxa1, and Spon1) by real-time PCR. Among these up-regulated genes, Spon1, which is a previously identified candidate gene for hypertension, was found to be up-regulated in kidney of human with diabetic nephropathy. Immunostaining of human biopsy samples demonstrated that protein expression of Spon1 was also markedly increased in kidneys of patients with both early and late HIVAN and diabetic nephropathy. Our studies suggest that analysis of both static and dynamic changes of gene expression profiles in disease progression avails another layer of information that could be utilized to gain a more comprehensive understanding of disease progression and identify potential biomarkers and drug targets.
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Altered spontaneous brain activity in primary open angle glaucoma: a resting-state functional magnetic resonance imaging study.
PLoS ONE
PUBLISHED: 01-01-2014
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Previous studies demonstrated that primary open angle glaucoma (POAG) is associated with abnormal brain structure; however, little is known about the changes in the local synchronization of spontaneous activity. The main objective of this study was to investigate spontaneous brain activity in patients with POAG using regional homogeneity (ReHo) analysis based on resting state functional magnetic resonance imaging (rs-fMRI).
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Association of HLA-DPB1 with scleroderma and its clinical features in Chinese population.
PLoS ONE
PUBLISHED: 01-01-2014
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Human leukocyte antigen DPB1 was reported to contain singly nucleotide polymorphisms conferring the strongest susceptibility to systemic sclerosis in Korean population. However, associations of specific DPB1 alleles with SSc vary in different ethnic populations. The aim of this study was to profile DPB1 alleles in Chinese population and to identify specific DPB1 alleles in association with SSc and clinical and serological features of SSc in Han Chinese. A cohort containing 338 patients with SSc and 480 gender-matched and unrelated controls were examined in the study. The HLA-DPB1 genotyping was performed with sequence-based typing method. Exact p-values were obtained (Fisher's test) from 2×2 tables of allele counts or allele carriers and disease status. Thirty eight DPB1 alleles were found in the cohort. DPB1*05:01 was the most common allele in this cohort. DPB1*03:01 and *13:01 were significantly increased in SSc. DPB1*13:01 association had already been described in other ethnic populations, whereas DPB1*03:01 was specific to Han Chinese patients with SSc. In addition, comparisons between SSc subsets indicated that patients carrying DPB1*03:01 were more likely to develop pulmonary fibrosis, DPB1*04 carriers were increased in SSc patients with anti-centromere autoantibodies and in contrast, SSc patients with homozygous DPB1*05:01 showed an opposite association with marginal significance.
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Associations of serum sclerostin and polymorphisms in the SOST gene with bone mineral density and markers of bone metabolism in postmenopausal Chinese women.
J. Clin. Endocrinol. Metab.
PUBLISHED: 01-01-2014
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The aims of this study were as follows: 1) to evaluate the association of serum sclerostin with bone mineral density (BMD) and markers of bone metabolism in postmenopausal Chinese women and 2) to observe the relationships of single-nucleotide polymorphisms (SNPs) within the sclerostin (SOST) gene with serum sclerostin, BMD, and markers of bone metabolism.
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Efficient Syntheses of Korupensamines A, B and Michellamine B by Asymmetric Suzuki-Miyaura Coupling Reactions.
J. Am. Chem. Soc.
PUBLISHED: 10-28-2013
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Efficient asymmetric Suzuki-Miyaura coupling reactions are employed for the first time in total syntheses of chiral biaryl natural products korupensamine A and B in combination with an effective diastereoselective hydrogenation, allowing ultimately a concise and stereoselective synthesis of michellamine B. Chiral monophosphorus ligands L1-3 are effective for the syntheses of a series of functionalized chiral biaryls by asymmetric Suzuki-Miyaura coupling reactions in excellent yields and enantioselectivities (up to 99% ee). The presence of a polar-? interaction between the highly polarized BOP group and the extended ? system of arylboronic acid coupling partner is believed to be important for the high enantioselectivity.
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Intracranial Calcifications and Hemorrhages: Characterization with Quantitative Susceptibility Mapping.
Radiology
PUBLISHED: 10-28-2013
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Purpose:To compare gradient-echo (GRE) phase magnetic resonance (MR) imaging and quantitative susceptibility mapping (QSM) in the detection of intracranial calcifications and hemorrhages.Materials and Methods:This retrospective study was approved by the institutional review board. Thirty-eight patients (24 male, 14 female; mean age, 33 years ± 16 [standard deviation]) with intracranial calcifications and/or hemorrhages diagnosed on the basis of computed tomography (CT), MR imaging (interval between examinations, 1.78 days ± 1.31), and clinical information were selected. GRE and QSM images were reconstructed from the same GRE data. Two experienced neuroradiologists independently identified the calcifications and hemorrhages on the QSM and GRE phase images in two randomized sessions. Sensitivity, specificity, and interobserver agreement were computed and compared with the McNemar test and ? coefficients. Calcification loads and volumes were measured to gauge intermodality correlations with CT.Results:A total of 156 lesions were detected: 62 hemorrhages, 89 calcifications, and five mixed lesions containing both hemorrhage and calcification. Most of these lesions (146 of 151 lesions, 96.7%) had a dominant sign on QSM images suggestive of a specific diagnosis of hemorrhage or calcium, whereas half of these lesions (76 of 151, 50.3%) were heterogeneous on GRE phase images and thus were difficult to characterize. Averaged over the two independent observers for detecting hemorrhages, QSM achieved a sensitivity of 89.5% and a specificity of 94.5%, which were significantly higher than those at GRE phase imaging (71% and 80%, respectively; P < .05 for both readers). In the identification of calcifications, QSM achieved a sensitivity of 80.5%, which was marginally higher than that with GRE phase imaging (71%; P = .08 and .10 for the two readers), and a specificity of 93.5%, which was significantly higher than that with GRE phase imaging (76.5%; P < .05 for both readers). QSM achieved significantly better interobserver agreements than GRE phase imaging in the differentiation of hemorrhage from calcification (?: 0.91 vs 0.55, respectively; P < .05).Conclusion:QSM is superior to GRE phase imaging in the differentiation of intracranial calcifications from hemorrhages and with regard to the sensitivity and specificity of detecting hemorrhages and the specificity of detecting calcifications.© RSNA, 2013Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13122640/-/DC1.
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Influence of hydrophilic amino acids and GC-content on expression of recombinant proteins used in vaccines against foot-and-mouth disease virus in Escherichia coli.
Biotechnol. Lett.
PUBLISHED: 10-01-2013
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Epitope-based protein expression in Escherichia coli can be improved by adjusting its amino acid composition and encoding genes. To that end, we analyzed 24 recombinant epitope proteins (rEPs) that carry multiple epitopes derived from VP1 protein of foot-and-mouth disease virus. High level expression of the rEPs was attributed to a high content of Arg, Asn, Asp and Thr, a low content of Gln, Pro and Lys, a high content of hydrophilic amino acids and a higher isoelectric point value resulting from abundant Arg. It is also attributed to the appropriate guanine and cytosine content in the encoding genes. The data provide a reference for adjusting the amino acid composition in designing epitope-based proteins used in vaccines and for adjusting the synonymous codons to improve their expressions in E. coli.
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Effects of semaphorin 3A on retinal pigment epithelial cell activity.
Invest. Ophthalmol. Vis. Sci.
PUBLISHED: 09-19-2013
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Semaphorin 3A (Sema3A), a chemorepellant guidance protein, has been shown to be crucial for neural and vascular remodeling. This study is designed to examine the effects of Sema3A on RPE cell activity both in vitro and in vivo.
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Doping alkaline-earth: a strategy of stabilizing hexagonal GdF3 at room temperature.
Dalton Trans
PUBLISHED: 09-13-2013
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Hexagonal GdF3 is a more efficient phosphor host compared with the traditional orthorhombic form but the hexagonal phase is thermodynamically unstable at room temperature. Herein, we present a strategy to stabilize hexagonal GdF3 by doping with alkaline-earth ions in a mild hydrothermal reaction system. The selection of the dopant, effect of the dopant amount and the mechanism of the phase transition was discussed in detail. The luminescence variation of GdF3:Eu was demonstrated to verify the phase transformation. Furthermore, the upconversion luminescence of the Sr-doped and undoped GdF3:Yb/Er was investigated.
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Kinetics of Th17 cytokines during telbivudine therapy in patients with chronic hepatitis B.
Viral Immunol.
PUBLISHED: 09-12-2013
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Th17 cells and the secreting cytokines play an important role in the immune response and inflammation that is induced by hepatitis B virus (HBV). However, it remains not fully elucidated how the antiviral agents affect Th17 cytokines and signal pathway. Telbivudine therapy has been proved to inhibit HBV replication effectively and to improve clinical outcome of chronic hepatitis B (CHB). Thus, in this study, the effect of decrease in viral load and liver dysfunction resulting from telbivudine treatment on Th17 cells and the related cytokines IL-17, IL-22, and IL-23 were analyzed. Peripheral blood mononuclear cells and serum from twenty-four CHB patients were harvested at 0, 12, 24, 36, and 48 weeks after initiation of telbivudine treatment. In parallel to the reduction of HBV DNA and normalization of serum ALT, significant declines in circulating HBV-specific Th17 cells and IL-22 production were found during antiviral therapy. The expression of serum IL-22 and IL-23, but not IL-17 also decreased during therapy. Our findings suggest that antiviral effect of telbivudine may attribute to both direct virus inhibition and regulation of inflammation, which further improve the understanding of pathogenesis of HBV infection and develop antiviral strategy for controlling viral hepatitis.
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Tunable blue-green-emitting Ba3LaNa(PO4)3F:Eu2+,Tb3+ phosphor with energy transfer for near-UV white LEDs.
Inorg Chem
PUBLISHED: 08-30-2013
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A series of Eu(2+) and Eu(2+)/Tb(3+) activated novel Ba3LaNa(PO4)3F phosphors have been synthesized by traditional solid state reaction. Rietveld structure refinement of the obtained phosphor indicates that the Ba3LaNa(PO4)3F host contains three kinds of Ba sites. The photoluminescence properties exhibit that the obtained phosphors can be efficiently excited in the range from 320 to 430 nm, which matches perfectly with the commercial n-UV LED chips. The critical distance of the Eu(2+) ions in Ba3LaNa(PO4)3F:Eu(2+) is calculated and the energy quenching mechanism is proven to be dipole-dipole interaction. Tunable blue-green emitting Ba3LaNa(PO4)3F:Eu(2+),Tb(3+) phosphor has been obtained by co-doping Eu(2+) and Tb(3+) ions into the host and varying their relative ratios. Compared with the Tb(3+) singly doped phosphor, the codoped phosphors have more intense absorption in the n-UV range and stronger emission of the Tb(3+) ions, which are attributed to the effective energy transfer from the Eu(2+) to Tb(3+) ions. The energy transfer from the Eu(2+) to Tb(3+) ions is demonstrated to be a dipole-quadrupole mechanism by the Inokuti-Hirayama (I-H) model. The Eu(2+) and Tb(3+) activated phosphor may be good candidates for blue-green components in n-UV white LEDs.
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Development and validation of a 96-well cellular assay for the discovery of ALDH1A1 inhibitors.
Assay Drug Dev Technol
PUBLISHED: 08-21-2013
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Retinoic acid, the active metabolite of vitamin A, plays important roles in various physiological and pathological processes. The two-step production of retinoic acid from vitamin A (retinol) is catalyzed by alcohol dehydrogenases and aldehyde dehydrogenases, which are potential therapeutic targets for numerous diseases, such as obesity, diabetes, and cancer. Currently, the lack of a suitable high-throughput cellular assay hinders efforts to identify therapeutic small molecular inhibitors of aldehyde dehydrogenase, such as ALDH1A1. In this report, we utilized high-content imaging technology and a commercially available cell permeable ALDH substrate to develop a 96-well cellular ALDH1A1 assay. This assay has a robust and sensitive readout and is amenable to automation. With this cellular assay, we identified potent selective ALDH1A1 inhibitors to explore the role of retinoic acid production in various preclinical disease models.
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Crystal structure and luminescent properties of a novel high efficiency blue-orange emitting NaCa2LuSi2O7F2:Ce3+,Mn2+ phosphor for ultraviolet light-emitting diodes.
Dalton Trans
PUBLISHED: 07-22-2013
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A series of NaCa2LuSi2O7F2:xCe(3+),yMn(2+) phosphors are firstly prepared by a high-temperature solid-state reaction technique. The Rietveld refinement analysis confirmed that the obtained phosphors have a pure crystalline phase with cuspidine-group structure. NaCa2LuSi2O7F2:xCe(3+),yMn(2+) phosphors can be efficiently excited by UV light and have two emission bands at about 410 and 600 nm. The luminescent properties of the singly-doped samples reveal that the Ce(3+) ions occupy two different Lu(3+) sites in the host lattice. We observed an efficient energy transfer from the Ce(3+) to Mn(2+) ions. The investigation revealed that the mechanism of the energy transfer was a resonant type via a nonradiative dipole-quadrupole interaction. The hues can be adjusted and white light can be obtained by tuning the concentration of Mn(2+) ions in the codoped phosphors through the energy transfer from the Ce(3+) to Mn(2+) ions, hinting a promising application of NaCa2LuSi2O7F2:xCe(3+),yMn(2+) as a single-component phosphor that can produce white light from UV-based LEDs.
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A novel orange-yellow-emitting Ba3Lu(PO4)3:Eu2+,Mn2+ phosphor with energy transfer for UV-excited white LEDs.
Dalton Trans
PUBLISHED: 07-17-2013
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Eu(2+)-Mn(2+) codoped orange-yellow-emitting Ba(3)Lu(PO(4))(3) phosphors were synthesized by a solid-state reaction. The synthesis, structure refinement, and luminescence properties of the obtained phosphor were first investigated in detail. The crystal structure was refined with a split-atom model, where the oxygen atoms are distributed over two partially occupied sites. The refinement confirmed that BLuP:0.005Eu(2+),0.06Mn(2+) has a cubic unit cell with space group I43d (no. 220), cell parameters a = b = c = 10.4025 Å and Z = 4. The luminescent properties reveal that the developed phosphor can efficiently convert UV photons in a broad range from 230 to 430 nm into orange-yellow emission. On the basis of the luminescence spectra and fluorescence decay curves, we confirm that the energy transfer process from the Eu(2+) to Mn(2+) ions takes place in the codoped Ba(3)Lu(PO(4))(3):Eu(2+),Mn(2+) phosphor, and the energy transfer efficiency increases with an increase in the Mn(2+) content. The possible energy transfer mechanism was proposed in terms of the experimental results and analysis. In particular, our developed phosphor contains a larger amount of the red-emitting component, compared with the commercial YAG:Ce phosphor, possessing favorable properties for application in warm white LEDs with low correlated color temperature.
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Synthesis, structure and photoluminescence properties of europium-, terbium-, and thulium-doped Ca3Bi(PO4)3 phosphors.
Dalton Trans
PUBLISHED: 07-16-2013
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A series of Eu(3+), Tb(3+), Tm(3+) singly and triply doped Ca3Bi(PO4)3 (CBP) phosphors were synthesized by solid-state reaction. Their structure and photoluminescence (PL) properties were first investigated in detail. Rietveld refinement analysis confirmed that the CBP has a cubic unit cell. Its space group was determined to be I4[combining macron]3d with cell parameters a = b = c = 9.941 Å and Z = 4. In addition, the Ca3Bi(PO4)3 shows both cation disorder and oxygen sublattice disorder. For the CBP:Eu(3+) phosphor, the charge transfer bands in the PLE spectra were different at 293 K and 4.3 K, and a model was presented to give a possible explanation for this phenomenon. CBP:Eu(3+) shows intense red emission due to (5)D0-(7)F2 transition and its integral emission intensity and quantum efficiency are higher than the commercial Y2O3:Eu(3+) phosphor under irradiation of 397 nm, indicating that the CBP:Eu(3+) phosphor might have potential application in the NUV range for solid-state lighting. The CBP:Tb(3+) and CBP:Tm(3+) phosphors show intense green and blue emission due to (5)D4-(7)F2 transition of the Tb(3+) ions and the (1)D2-(3)F4 transition of the Tm(3+) ions, respectively. The energy transfer from the Tb(3+) to Eu(3+) ions was also validated by the spectra and decay curves of the Tb(3+) ions. Tunable emission colors were obtained by triply doping Eu(3+), Tb(3+) and Tm(3+) activators in a single host and adjusting their relative ratio.
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Spectral tuning of the n-UV convertible oxynitride phosphor: orange color emitting realization via an energy transfer mechanism.
Phys Chem Chem Phys
PUBLISHED: 07-16-2013
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Near-UV convertible Eu(3+)-activated orange oxynitride phosphors have been obtained via a Ce(3+)? Tb(3+)? Eu(3+) energy transfer mechanism. The Tb(3+) ions play the role of an energy transfer bridge to connect the Ce(3+) and Eu(3+) ion pairs, and an optimal concentration of the Tb(3+) ion is necessary for maximum intensity of the Eu(3+) ion emission.
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Characterization and fine mapping of a novel rice narrow leaf mutant nal9.
J Integr Plant Biol
PUBLISHED: 06-22-2013
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A narrow leaf mutant was isolated from transgenic rice (Oryza sativa L.) lines carrying a T-DNA insertion. The mutant is characterized by narrow leaves during its whole growth period, and was named nal9 (narrow leaf 9). The mutant also has other phenotypes, such as light green leaves at the seedling stage, reduced plant height, a small panicle and increased tillering. Genetic analysis revealed that the mutation is controlled by a single recessive gene. A hygromycin resistance assay showed that the mutation was not caused by T-DNA insertion, so a map-based cloning strategy was employed to isolate the nal9 gene. The mutant individuals from the F? generations of a cross between the nal9 mutant and Longtepu were used for mapping. With 24 F? mutants, the nal9 gene was preliminarily mapped near the marker RM156 on the chromosome 3. New INDEL markers were then designed based on the sequence differences between japonica and indica at the region near RM156. The nal9 gene was finally located in a 69.3?kb region between the markers V239B and V239G within BAC OJ1212_C05 by chromosome walking. Sequence and expression analysis showed that an ATP-dependent Clp protease proteolytic subunit gene (ClpP) was most likely to be the nal9 gene. Furthermore, the nal9 mutation was rescued by transformation of the ClpP cDNA driven by the 35S promoter. Accordingly, the ClpP gene was identified as the NAL9 gene. Our results provide a basis for functional studies of NAL9 in future work.
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Predictors of visual response to intravitreal bevacizumab for treatment of neovascular age-related macular degeneration.
J Ophthalmol
PUBLISHED: 06-20-2013
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Purpose. To identify the predictors of visual response to the bevacizumab treatment of neovascular age-related macular degeneration (AMD). Design. A cohort study within the Neovascular AMD Treatment Trial Using Bevacizumab (NATTB). Methods. This was a multicenter trial including 144 participants from the NATTB study. Visual outcomes measured by change in visual acuity (VA) score, proportion gaining ?15 letters, and change in central retinal thickness (CRT) were compared among groups according to the baseline, demographic, and ocular characteristics and genotypes. Results. Mean change in the VA score was 9.2 ± 2.3 SD letters with a total of 46 participants (31.9%) gaining ?15 letters. Change in median CRT was -81.5? ? m. Younger age, lower baseline VA score, shorter duration of neovascular AMD, and TT genotype in rs10490924 were significantly associated with greater VA score improvement (P = 0.028, P < 0.001, P = 0.02, and P = 0.039, resp.). Lower baseline VA score and TT genotype in rs10490924 were significantly associated with a higher likelihood of gaining ?15 letters (P = 0.028, and P = 0.021, resp.). Conclusions. Baseline VA and genotype of rs10490924 were both important predictors for visual response to bevacizumab at 6 months. This trial is registered with the Registration no. NCT01306591.
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Palmitoyl-protein thioesterase 1 (PPT1): An obesity-induced rat testicular marker of reduced fertility.
Mol. Reprod. Dev.
PUBLISHED: 06-12-2013
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Male obesity may lead to declines in testosterone levels, reproductive hormonal profile, and semen quantity. To assess the effects of obesity on spermatogenesis, Sprague-Dawley rats fed a high-fat diet served as a model of induced obesity. The litter sizes for females mated to obese males were significantly lower as compared to females mated with normal-diet-fed controls. Their serum high-density lipoprotein, low-density lipoprotein, cholesterol, and estradiol levels increased in obese males, but testosterone and follicle-stimulating hormone levels decreased. Testicular morphology disruptions included Sertoli-cell atrophy, disrupted tight junctions, and mitochondrial degeneration in spermatogenic cells. To further investigate the molecular mechanisms leading to high-fat-diet-induced changes, we employed testicular proteomic analysis on rats fed both types of diet. Three spots were up-regulated in rats fed a high-fat diet whereas two others were downregulated. One of the upregulated spots was palmitoyl-protein thioesterase 1 (PPT1), a lipoprotein metabolizing related enzyme localized to Sertoli cells. In a Sertoli-cell line cultured in a high-fat supplemented medium, PPT1 abundance was accompanied by increases in the endocytic vesicle-associated protein, clathrin, and decreases in the tight junctional proteins, ZO-1 and occludin. In conclusion, declines in rat male fertility induced by a high-fat diet are associated with an altered testicular protein expression pattern as well as disruption of testicular Sertoli-cell and spermatogenic-cell morphology. PPT1 expression may provide a testicular marker of reduced fertility in obese males, as increases in its expression may be detrimental to Sertoli-cell function during spermatogenesis. Mol. Reprod. Dev. 2013. © 2013 Wiley Periodicals, Inc.
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Noise Effects In Various Quantitative Susceptibility Mapping Methods.
IEEE Trans Biomed Eng
PUBLISHED: 06-12-2013
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Various regularization methods have been proposed for single-orientation quantitative susceptibility mapping (QSM), which is an ill-posed magnetic field to susceptibility source inverse problem. Noise amplification, a major issue in inverse problems, manifests as streaking artifacts and quantification errors in QSM and has not been comparatively evaluated in these algorithms. In this paper, various QSM methods were systematically categorized for noise analysis. Six representative QSM methods were selected from four categories: two non-Bayesian methods with alteration or approximation of the dipole kernel to overcome the ill conditioning; four Bayesian methods using a general mathematical prior or a specific physical structure prior to select a unique solution, and using a data fidelity term with or without noise weighting. The effects of noise in these QSM methods were evaluated by reconstruction errors in simulation and image quality in 50 consecutive human subjects. Bayesian QSM methods with noise weighting consistently reduced root mean squared errors in numerical simulations and increased image quality scores in the human brain images, when compared to non-Bayesian methods and to corresponding Bayesian methods without noise weighting (p 0.001). In summary, noise effects in QSM can be reduced using Bayesian methods with proper noise weighting.
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pH/temperature sensitive magnetic nanogels conjugated with Cy5.5-labled lactoferrin for MR and fluorescence imaging of glioma in rats.
Biomaterials
PUBLISHED: 05-17-2013
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Glioma is the most common primary brain tumor and causes a disproportionate level of morbidity and mortality across a wide range of individuals. From previous clinical practices, definition of glioma margin is the key point for surgical resection. In order to outline the exact margin of glioma and provide a guide effect for the physicians both at pre-surgical planning stage and surgical resection stage, pH/temperature sensitive magnetic nanogels conjugated with Cy5.5-labled lactoferrin (Cy5.5-Lf-MPNA nanogels) were developed as a promising contrast agent. Due to its pH/te mperature sensitivity, Cy5.5-Lf-MPNA nanogels could change in its hydrophilic/hydrophobic properties and size at different pH and temperatures. Under physiological conditions (pH 7.4, 37 °C), Cy5.5-Lf-MPNA nanogels were hydrophilic and swollen, which could prolong the blood circulation time. In the acidic environment of tumor tissues (pH 6.8, 37 °C), Cy5.5-Lf-MPNA nanogels became hydrophobic and shrunken, which could be more easily accumulated in tumor tissue and internalized by tumor cells. In addition, lactoferrin, an effective targeting ligand for glioma, provides active tumor targeting ability. In vivo studies on rats bearing in situ glioma indicated that the MR/fluorescence imaging with high sensitivity and specificity could be acquired using Cy5.5-Lf-MPNA nanogels due to active targeting function of the Lf and enhancement of cellular uptake by tailoring the hydrophilic/hydrophobic properties of the nanogels. With good biocompatibility shown by cytotoxicity assay and histopathological analysis, Cy5.5-Lf-MPNA nanogels are hopeful to be developed as a specific and high-sensitive contrast agent for preoperative MRI and intraoperative fluorescence imaging of glioma.
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Solid-state high performance flexible supercapacitors based on polypyrrole-MnO2-carbon fiber hybrid structure.
Sci Rep
PUBLISHED: 05-01-2013
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A solid-state flexible supercapacitor (SC) based on organic-inorganic composite structure was fabricated through an "in situ growth for conductive wrapping" and an electrode material of polypyrrole (PPy)-MnO2 nanoflakes-carbon fiber (CF) hybrid structure was obtained. The conductive organic material of PPy greatly improved the electrochemical performance of the device. With a high specific capacitance of 69.3?F cm(-3) at a discharge current density of 0.1?A cm(-3) and an energy density of 6.16 × 10(-3)?Wh cm(-3) at a power density of 0.04?W cm(-3), the device can drive a commercial liquid crystal display (LCD) after being charged. The organic-inorganic composite active materials have enormous potential in energy management and the "in situ growth for conductive wrapping" method might be generalized to open up new strategies for designing next-generation energy storage devices.
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Tailoring the coupling between localized and propagating surface plasmons: realizing Fano-like interference and high-performance sensor.
Opt Express
PUBLISHED: 04-24-2013
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Surface plasmon modes originated from various metallic nanostructures possess unique features of strong nanoscale light confinement and enhancement with tunable energy, which make them attractive and promising for a variety of applications such as sensing, solar cell, and lasing. Here, we have investigated the interaction between localized and propagating surface plasmons in a structure consisting of a gold nanobar array and a thick gold film, separated by a silica dielectric spacer layer. It is found that the reflection spectrum of the designed plasmonic structure can be readily tailored by changing the gold nanobar size, array period and the spacer layer thickness. Moreover, the strong coupling between the localized and propagating modes can result in an anticrossing behavior and even induce a Fano-like asymmetric lineshape. Importantly, the sensitivity and the figure of merit (FoM) of this plasmonic system can reach as high as 936 nm/RIU and 112, respectively. Our study offers a new, simple, efficient and controllable way to design the plasmonic systems with desired modes coupling and spectral lineshapes for different applications.
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Targeting sirtuin-1 in Huntingtons disease: rationale and current status.
CNS Drugs
PUBLISHED: 04-04-2013
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Huntingtons disease (HD) is an autosomal dominant hereditary disease caused by a trinucleotide repeat mutation in the huntingtin gene that results in an increased number of glutamine residues in the N terminus of huntingtin protein. Mutant huntingtin leads to progressive impairment of motor function, cognitive dysfunction, and neuropsychiatric disturbance. There are no disease-modifying treatments available. During the past decade, sirtuin-1 (SIRT1) has been the focus of intense investigation and discussion because it regulates longevity in multiple organisms and has shown beneficial effects in a variety of models of neurodegenerative disorders. Studies in different animal models provide convincing evidence that SIRT1 protects neurons in mouse models of HD as well as in Caenorhabditis elegans, although controversial results were reported in a fly model. Indeed, many connections exist between the deacetylation function of SIRT1 and its role in neuroprotection. As a result, pharmacological interventions targeting SIRT1 might become promising strategies to combat HD. This review summarizes recent progress in SIRT1 research, with a focus on the specificity of this protein as a potential therapeutic target for HD, as well as existing challenges for developing SIRT1 modulators for clinical use.
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Cable-type supercapacitors of three-dimensional cotton thread based multi-grade nanostructures for wearable energy storage.
Adv. Mater. Weinheim
PUBLISHED: 03-23-2013
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A novel cable-type flexible supercapacitor with excellent performance is fabricated using 3D polypyrrole(PPy)-MnO2 -CNT-cotton thread multi-grade nanostructure-based electrodes. The multiple supercapacitors with a high areal capacitance 1.49 F cm(-2) at a scan rate of 1 mV s(-1) connected in series and in parallel can successfully drive a LED segment display. Such an excellent performance is attributed to the cumulative effect of conducting single-walled carbon nanotubes on cotton thread, active mesoporous flower-like MnO2 nanoplates, and PPy conductive wrapping layer improving the conductivity, and acting as pseudocapacitance material simultaneously.
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[Expression and distribution of cysteinyl leukotriene receptors CysLT1R and CysLT2R, and GPR17 in brain of Parkinson disease model mice].
Zhejiang Da Xue Xue Bao Yi Xue Ban
PUBLISHED: 03-19-2013
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To examine the spatiotemporal profiles and localization of CysLT1R, CysLT2R and GPR17 in mice with 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced Parkinson disease (PD).
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Inorganic-salt-induced morphological transformation and luminescent performance of GdF3 nanostructures.
Dalton Trans
PUBLISHED: 03-19-2013
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Inorganic-salt-induced morphological evolution of GdF3 crystals was demonstrated for the first time in a mild hydrothermal process. By varying the amount of inorganic salt, the GdF3 crystals could transform from uniform elliptic nanostructures to submicroplates. The increase of ionic strength, hindered diffusion of reactant ions, and selectively adsorption of barium cations were responsible for such morphological transformation. Besides, relatively low concentration of F(-) contributed to the formation of GdF3 in the presence of foreign inorganic salt, instead of ternary fluoride. In addition, the luminescence properties of the as-formed nanostructures were investigated by singly doping Eu(3+), Tb(3+), and Dy(3+) into the GdF3 matrix.
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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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