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Find video protocols related to scientific articles indexed in Pubmed.
Rhodium(iii)-catalyzed C-H/C-C activation sequence: vinylcyclopropanes as versatile synthons in direct C-H allylation reactions.
Chem. Commun. (Camb.)
PUBLISHED: 11-11-2014
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Succession of C-H activation and C-C activation was achieved by using a single rhodium(iii) catalyst. Vinylcyclopropanes were used as versatile coupling partners. Mechanistic studies suggest that the olefin insertion step is rate-determining and a facile ?-carbon elimination is involved, which represents a novel ring opening mode of vinylcyclopropanes.
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Visceral fat accumulation is associated with different pathological subtypes of renal cell carcinoma (RCC): a multicentre study in China.
BJU Int.
PUBLISHED: 11-11-2014
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To investigate whether visceral obesity is associated with certain histological subtypes of renal cell carcinoma (RCC) ina multicentre Chinese cohort.
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Diagnostic significance of apparent diffusion coefficient values with diffusion weighted MRI in breast cancer: a meta- analysis.
Asian Pac. J. Cancer Prev.
PUBLISHED: 10-24-2014
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Apparent diffusion coefficient (ADC) values of nodes in diffusion-weighted imaging (DWI) are widely used in differentiating metastatic from non-metastatic lymph nodes. The purpose of this meta-analysis was to demonstrate whether DWI could contribute to the precise diagnosis of breast cancer (BC) with and without lymph node metastasis (LNM).
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[Determining the concentration of coating solution attaching to honeycomb denuder in summer in Tianjin].
Huan Jing Ke Xue
PUBLISHED: 10-24-2014
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The study on determining the concentration of coating solution attaching to honeycomb denuder was conducted, from 1 July to 31 August, 2013, at the roof of Lihua building at Nankai University in Tianjin. The results of experiment showed that the optimized concentration of sodium carbonate coated on the honeycomb denuder was 3%, and the optimized concentration of citric acid was 6%. The contrast sampling results of PM2.5 between honeycomb denuder system and conventional method showed that 86% of the concentration of PM2.5 samples obtained by honeycomb denuder system were less than those obtained by conventional method, the main reasons may include that: (1) the majority of acid/alkaline gases were removed, so they could neither react with the enriched particles on the sampling membrane nor be adsorbed on particles; (2) parts of the particles were captured by the denuder during sampling; (3) the removal of acid/alkaline gases disturbed the state of equilibrium between gas- and particle-phases which may lead to the volatilization of some particles.
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[Treatment of combined hyperlipidemia patients by jiangzhi tongluo soft capsule combined atorvastatin calcium tablet: a clinical study].
Zhongguo Zhong Xi Yi Jie He Za Zhi
PUBLISHED: 10-23-2014
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To evaluate the efficacy and safety of using Jiangzhi Tongluo Soft Capsule (JTSC) combined with Atorvastatin Calcium Tablet (ACT) or ACT alone in treatment of combined hyperlipidemia.
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[A comparative study of the laparoscopic appearance and anatomy of the autonomic nervous in normal males].
Zhonghua Wai Ke Za Zhi
PUBLISHED: 09-30-2014
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To further understand the anatomical basis of pelvic autonomic nerve preservation.
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Metal-organic framework derived hybrid Co3O4-carbon porous nanowire arrays as reversible oxygen evolution electrodes.
J. Am. Chem. Soc.
PUBLISHED: 09-22-2014
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Hybrid porous nanowire arrays composed of strongly interacting Co3O4 and carbon were prepared by a facile carbonization of the metal-organic framework grown on Cu foil. The resulting material, possessing a high surface area of 251 m(2) g(-1) and a large carbon content of 52.1 wt %, can be directly used as the working electrode for oxygen evolution reaction without employing extra substrates or binders. This novel oxygen evolution electrode can smoothly operate in alkaline solutions (e.g., 0.1 and 1.0 M KOH), affording a low onset potential of 1.47 V (vs reversible hydrogen electrode) and a stable current density of 10.0 mA cm(-2) at 1.52 V in 0.1 M KOH solution for at least 30 h, associated with a high Faradaic efficiency of 99.3%. The achieved ultrahigh oxygen evolution activity and strong durability, with superior performance in comparison to the state-of-the-art noble-metal/transition-metal and nonmetal catalysts, originate from the unique nanowire array electrode configuration and in situ carbon incorporation, which lead to the large active surface area, enhanced mass/charge transport capability, easy release of oxygen gas bubbles, and strong structural stability. Furthermore, the hybrid Co3O4-carbon porous nanowire arrays can also efficiently catalyze oxygen reduction reaction, featuring a desirable four-electron pathway for reversible oxygen evolution and reduction, which is potentially useful for rechargeable metal-air batteries, regenerative fuel cells, and other important clean energy devices.
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CdS Nanoflake Arrays for Highly Efficient Light Trapping.
Adv. Mater. Weinheim
PUBLISHED: 08-28-2014
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CdS nanoflake arrays exhibit unprecedented light absorption capability, and they can serve as a scaffold to load thin organic absorbers for extraordinarily high light absorption. Resultantly, the hybrid solar cell consisting of NFAs and organic absorber yields a ten-time high short-circuit photocurrent compared to the counterpart device with a common planar structure.
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Excellent capacitive performance of a three-dimensional hierarchical porous graphene/carbon composite with a superhigh surface area.
Chemistry
PUBLISHED: 08-25-2014
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Three-dimensional hierarchical porous graphene/carbon composite was successfully synthesized from a solution of graphene oxide and a phenolic resin by using a facile and efficient method. The morphology, structure, and surface property of the composite were investigated intensively by a variety of means such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption, Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). It is found that graphene serves as a scaffold to form a hierarchical pore texture in the composite, resulting in its superhigh surface area of 2034?m(2) g(-1), thin macropore wall, and high conductivity (152?S?m(-1)). As evidenced by electrochemical measurements in both EMImBF4 ionic liquid and KOH electrolyte, the composite exhibits ideal capacitive behavior, high capacitance, and excellent rate performance due to its unique structure. In EMImBF4 , the composite has a high energy density of up to 50.1?Wh?kg(-1) and also possesses quite stable cycling stability at 100?°C, suggesting its promising application in high-temperature supercapacitors. In KOH electrolyte, the specific capacitance of this composite can reach up to an unprecedented value of 186.5?F?g(-1), even at a very high current density of 50?A?g(-1), suggesting its prosperous application in high-power applications.
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Preclinical pharmacology and toxicology study of Ad-hTERT-E1a-Apoptin, a novel dual cancer-specific oncolytic adenovirus.
Toxicol. Appl. Pharmacol.
PUBLISHED: 08-20-2014
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Clinical studies have demonstrated that conditionally replicating adenovirus is safe. We constructed an oncolytic adenovirus, Ad-hTERT-E1a-Apoptin, using a cancer-specific promoter (human telomerase reverse transcriptase promoter, hTERTp) and a cancer cell-selective apoptosis-inducing gene (Apoptin). Ad-hTERT-E1a-Apoptin was proven effective both in vitro and in vivo in our previous study. In this study, the preclinical safety profiles of Ad-hTERT-E1a-Apoptin in animal models were investigated. At doses of 5.0×10(8), 2.5×10(9), and 1.25×10(10) viral particles (VP)/kg, Ad-hTERT-E1a-Apoptin had no adverse effects on mouse behavior, muscle cooperation, sedative effect, digestive system, and nervous systems, or on beagle cardiovascular and respiratory systems at 5.0×10(8), 2.5×10(9), and 1.25×10(10) VP/kg doses. In acute toxicity tests in mice, the maximum tolerated dose>5×10(10) VP/kg. There was no inflammation or ulceration at the injection sites within two weeks. In repeat-dose toxicological studies, the no observable adverse effect levels of Ad-hTERT-E1a-Apoptin in rats (1.25×10(10) VP/kg) and beagles (2.5×10(9) VP/kg) were 62.5- and 12.5-fold of the proposed clinical dose, respectively. The anti-virus antibody was produced in animal sera. Bone marrow examination revealed no histopathological changes. Guinea pigs sensitized by three repeated intraperitoneal injections of 1.35×10(10) VP/mL Ad-hTERT-E1a-Apoptin each and challenged by one intravenous injection of 1.67×10(8) VP/kg Ad-hTERT-E1a-Apoptin did not exhibit any sign of systemic anaphylaxis. Our data from different animal models suggest that Ad-hTERT-E1a-Apoptin is a safe anti-tumor therapeutic agent.
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Double open-circuit voltage of three-dimensional ZnO/CdTe solar cells by a balancing depletion layer.
ACS Appl Mater Interfaces
PUBLISHED: 08-18-2014
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Three-dimensional (3D) heterojunction solar cells (HSCs) were fabricated by thermal deposition of a compact CdTe layer onto ZnO nanorods (NRs). Although the 3D architecture obviously improves the short-circuit current of HSCs, the open-circuit voltage is rather low, and this problem can be addressed by inserting an intermediate layer between ZnO NRs and the CdTe layer. On the basis of experimental and theoretical analyses, we found that the low open-circuit voltage mainly arose from the incomplete depletion layer and serious recombination of carriers at the CdTe/ZnO interface. The CdS intermediate layer can redistribute the depletion regions and eliminate the interface defects, thus remarkably improving the open-circuit voltage.
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Synthesis of highly active and stable spinel-type oxygen evolution electrocatalysts by a rapid inorganic self-templating method.
Chemistry
PUBLISHED: 08-14-2014
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Composition-adjustable spinel-type metal oxides, Mnx Co3-x O4-? (x=0.8-1.4), were synthesized in ethanol solutions by a rapid inorganic self-templating mechanism using KCl nanocrystals as the structure-directing agent. The Mnx Co3?x O4?? materials showed ultrahigh oxygen evolution activity and strong durability in alkaline solutions, and are capable of delivering a current density of 10?mA?cm(-2) at 1.58?V versus the reversible hydrogen electrode in 0.1?M KOH solution, which is superior in comparison to IrO2 catalysts under identical experimental conditions, and comparable to the most active noble-metal and transition-metal oxygen evolution electrocatalysts reported so far. The high performance for catalytic oxygen evolution originates from both compositional and structural features of the synthesized materials. The moderate content of Mn doping into the spinel framework led to their improved electronic conductivity and strong oxidizing ability, and the well-developed porosity, accompanied with the high affinity between OH(-) reactants and catalyst surface, contributed to the smooth mass transport, thus endowing them with superior oxygen evolution activity.
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Synthesis and evaluation of novel podophyllotoxin derivatives as potential antitumor agents.
Eur J Med Chem
PUBLISHED: 08-04-2014
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Cancer multidrug resistance (MDR) is a common cause of treatment failure in cancer patients. Increased expression of permeability glycoprotein (P-gp), which is also known as MDR-1, is the main cause of multidrug resistance. Podophyllotoxin derivatives hold great promise in the battle to overcome multidrug resistance, as they can induce cytotoxicity through multiple mechanisms. Here, we synthesized sixteen novel podophyllotoxin derivatives and evaluated their cytotoxicities in human cancer cell lines, HeLa, K562 and K562/A02. Some of these compounds were more potent than etoposide, a clinically relevant inhibitor of DNA repair enzymes. In particular, compound 5p exhibited the most potent activity toward drug-resistant K562/A02 cells, as it robustly inhibited tumor cell proliferation and induced apoptosis. Furthermore, preliminary investigation suggested that 5p inhibited the expression of MDR-1 in K562/A02 cells more effectively than etoposide.
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Advancing the Electrochemistry of the Hydrogen-Evolution Reaction through Combining Experiment and Theory.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-09-2014
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The electrocatalytic hydrogen-evolution reaction (HER), as the main step of water splitting and the cornerstone of exploring the mechanism of other multi-electron transfer electrochemical processes, is the subject of extensive studies. A large number of high-performance electrocatalysts have been developed for HER accompanied by recent significant advances in exploring its electrochemical nature. Herein we present a critical appraisal of both theoretical and experimental studies of HER electrocatalysts with special emphasis on the electronic structure, surface (electro)chemistry, and molecular design. It addresses the importance of correlating theoretical calculations and electrochemical measurements toward better understanding of HER electrocatalysis at the atomic level. Fundamental concepts in the computational quantum chemistry and its relation to experimental electrochemistry are also presented along with some featured examples.
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Species Differences in Cannabinoid Receptor 2 and Receptor Responses to Cocaine Self-Administration in Mice and Rats.
Neuropsychopharmacology
PUBLISHED: 07-03-2014
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The discovery of functional cannabinoid receptor 2 (CB2R) in brain suggests a potential new therapeutic target for neurological and psychiatric disorders. However, recent findings in experimental animals appear controversial. Here we report that there are significant species differences in CB2R mRNA splicing and expression, protein sequences, and the receptor responses to CB2R ligands in mice and rats. Systemic administration of JWH133, a highly-selective CB2R agonist, significantly and dose-dependently inhibited intravenous cocaine self-administration under a fixed-ratio (FR) schedule of reinforcement in mice, but not in rats. However, under a progressive-ratio (PR) schedule of reinforcement, JWH133 significantly increased break-point for cocaine self-administration in rats, but decreased it in mice. To explore the possible reasons for these conflicting findings, we examined CB2R gene expression and receptor structure in the brain. We found novel rat-specific CB2C and CB2D mRNA isoforms in addition to CB2?A and CB2B mRNA isoforms of mice. In situ hybridization RNAscope assays found higher levels of CB2R mRNA in different brain regions and cell types in mice than in rats. By comparing CB2R-encoding regions, we observed a premature stop codon in the mouse CB2R gene, which truncated 13 amino acid residues including a functional autophosphorylation site in the intracellular C-terminus. These findings suggest that species differences in the splicing and expression of CB2R genes and receptor structures may in part explain the different effects of CB2R-selective ligands on cocaine self-administration in mice and rats.Neuropsychopharmacology accepted article preview online, 06 November 2014. doi:10.1038/npp.2014.297.
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Tumor-derived exosomes promote tumor progression and T-cell dysfunction through the regulation of enriched exosomal microRNAs in human nasopharyngeal carcinoma.
Oncotarget
PUBLISHED: 07-01-2014
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Tumor-derived exosomes contain biologically active proteins and messenger and microRNAs (miRNAs). These particles serve as vehicles of intercellular communication and are emerging mediators of tumorigenesis and immune escape. Here, we isolated 30-100 nm exosomes from the serum of patients with nasopharyngeal carcinoma (NPC) or the supernatant of TW03 cells. Increased circulating exosome concentrations were correlated with advanced lymphoid node stage and poor prognosis in NPC patients (P< 0.05). TW03-derived exosomes impaired T-cell function by inhibiting T-cell proliferation and Th1 and Th17 differentiation and promoting Treg induction by NPC cells in vitro. These results are associated with decreases in ERK, STAT1, and STAT3 phosphorylation and increases in STAT5 phosphorylation in exosome-stimulated T-cells. TW03-derived exosomes increased the proinflammatory cytokines IL-1?, IL-6, and IL-10 but decreased IFN?, IL-2, and IL-17 release from CD4+ or CD8+ T-cells. Furthermore, five commonly over-expressed miRNAs were identified in the exosomes from patient sera or NPC cells: hsa-miR-24-3p, hsa-miR-891a, hsa-miR-106a-5p, hsa-miR-20a-5p, and hsa-miR-1908. These over-expressed miRNA clusters down-regulated the MARK1 signaling pathway to alter cell proliferation and differentiation. Overall, these observations reveal the clinical relevance and prognostic value of tumor-derived exosomes and identify a unique intercellular mechanism mediated by tumor-derived exosomes to modulate T-cell function in NPC.
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Enhanced Visible-Light Photocatalytic H2 Production by Znx Cd1-x S Modified with Earth-Abundant Nickel-Based Cocatalysts.
ChemSusChem
PUBLISHED: 06-23-2014
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The application of various earth-abundant Ni species, such as NiS, Ni, Ni(OH)2 , and NiO, as a co-catalyst in a Znx Cd1-x S system for visible-light photocatalytic H2 production was investigated for the first time. The loading of Ni or NiS enhanced the photocatalytic activity of Znx Cd1-x S because they could promote the electron transfer at the interface with Znx Cd1-x S and catalyze the H2 evolution. Surprisingly, Ni(OH)2 -loaded Znx Cd1-x S exhibits a very high photocatalytic H2 -production rate of 7160??mol?h(-1) ?g(-1) with a quantum efficiency of 29.5?% at 420?nm, which represents one of the most efficient metal sulfide photocatalysts without a Pt co-catalyst to date. This outstanding activity arises from the pronounced synergetic effect between Ni(OH)2 and metallic Ni formed in?situ during the photocatalytic reaction. However, the loading of NiO deactivated the activity of Znx Cd1-x S because of their unmatched conduction band positions. This paper reports the optimization of the Znx Cd1-x S system by selecting an appropriate Ni-based co-catalyst, Ni(OH)2 , from a series of Ni species to achieve the highest photocatalytic H2 -production activity for the first time and also reveals the roles of these Ni species in the photocatalytic activity.
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Observation of active sites for oxygen reduction reaction on nitrogen-doped multilayer graphene.
ACS Nano
PUBLISHED: 06-03-2014
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Active sites and the catalytic mechanism of nitrogen-doped graphene in an oxygen reduction reaction (ORR) have been extensively studied but are still inconclusive, partly due to the lack of an experimental method that can detect the active sites. It is proposed in this report that the active sites on nitrogen-doped graphene can be determined via the examination of its chemical composition change before and after ORR. Synchrotron-based X-ray photoelectron spectroscopy analyses of three nitrogen-doped multilayer graphene samples reveal that oxygen reduction intermediate OH(ads), which should chemically attach to the active sites, remains on the carbon atoms neighboring pyridinic nitrogen after ORR. In addition, a high amount of the OH(ads) attachment after ORR corresponds to a high catalytic efficiency and vice versa. These pinpoint that the carbon atoms close to pyridinic nitrogen are the main active sites among the different nitrogen doping configurations.
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Genomewide analysis of LATERAL ORGAN BOUNDARIES Domain gene family in Zea mays.
J. Genet.
PUBLISHED: 05-21-2014
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The investigation of transcription factor (TF) families is a major focus of postgenomic research. The plant-specific ASYMMETRIC LEAVES2-LIKE (ASL) / LATERAL ORGAN BOUNDARIES Domain (LBD) proteins constitute a major zincfinger-like-domain transcription factor family, and regulate diverse biological processes in plants. However, little is known about LBD genes in maize (Zea mays). In this study, a total of 44 LBD genes were identified in maize genome and were phylogenetically clustered into two groups (I and II), together with LBDs from Arabidopsis. The predicted maize LBDs were distributed across all the 10 chromosomes with different densities. In addition, the gene structures of maize LBDs were analysed. The expression profiles of the maize LBD genes under normal growth conditions were analysed by microarray data and qRT-PCR. The results indicated that LBDs might be involved in various aspects of physiological and developmental processes in maize. To our knowledge, this is the first report of a genomewide analysis of the maize LBD gene family, which would provide valuable information for understanding the classification and putative functions of the gene family.
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Dendritic Silica Particles with Center-Radial Pore Channels: Promising Platforms for Catalysis and Biomedical Applications.
Small
PUBLISHED: 05-01-2014
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Dendritic silica micro-/nanoparticles with center-radial pore structures, a kind of newly created porous material, have attracted considerable attention owing to their unique open three-dimensional dendritic superstructures with large pore channels and highly accessible internal surface areas compared with conventional mesoporous silica nanoparticles (MSNs). They are very promising platforms for a variety of applications in catalysis and nanomedicine. In this review, their unique structural characteristics and properties are first analyzed, then novel and interesting synthesis methods associated with the possible formation mechanisms are summarized to provide material scientists some inspiration for the preparation of this kind of dendritic particles. Subsequently, a few examples of interesting applications are presented, mainly in catalysis, biomedicine, and other important fields such as for sacrificial templates and functional coatings. The review is concluded with an outlook on the prospects and challenges in terms of their controlled synthesis and potential applications.
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Toward design of synergistically active carbon-based catalysts for electrocatalytic hydrogen evolution.
ACS Nano
PUBLISHED: 05-01-2014
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Replacement of precious Pt catalyst with cost-effective alternatives would be significantly beneficial for hydrogen production via electrocatalytic hydrogen evolution reaction (HER). All candidates thus far are exclusively metallic catalysts, which suffer inherent corrosion and oxidation susceptibility during acidic proton-exchange membrane electrolysis. Herein, based on theoretical predictions, we designed and synthesized nitrogen (N) and phosphorus (P) dual-doped graphene as a nonmetallic electrocatalyst for sustainable and efficient hydrogen production. The N and P heteroatoms could coactivate the adjacent C atom in the graphene matrix by affecting its valence orbital energy levels to induce a synergistically enhanced reactivity toward HER. As a result, the dual-doped graphene showed higher electrocatalytic HER activity than single-doped ones and comparable performance to some of the traditional metallic catalysts.
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Adiponectin protects rat heart from left ventricular remodeling induced by chronic intermittent hypoxia via inhibition of TGF-?/smad2/3 pathway.
J Thorac Dis
PUBLISHED: 04-29-2014
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Obstructive sleep apnea syndrome (OSAS) is associated with many cardiovascular disorders. Chronic intermittent hypoxia (CIH) is the primary player in OSAS of the many associated factors. This study was in order to investigate the effects of the Adiponectin (Ad) on left ventricular remodeling induced by CIH.
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Fe-N decorated hybrids of CNTs grown on hierarchically porous carbon for high-performance oxygen reduction.
Adv. Mater. Weinheim
PUBLISHED: 04-23-2014
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An Fe-N-decorated hybrid material of carbon nanotubes (CNTs) grown in situ from porous carbon microblocks is designed and constructed. This material successfully combines the desirable merits for oxygen reduction reaction (ORR), such as highly active Fe-N species, good conductivity, large pore size, and sufficient surface area. These structural advantages give this low-priced material an outstanding catalytic performance for ORR closely comparable with Pt/C of the same quantity.
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Primary invasive carcinoma associated with penoscrotal extramammary Paget's disease: a clinicopathological analysis of 56 cases.
BJU Int.
PUBLISHED: 04-16-2014
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To investigate the clinicopathological features, therapeutic strategies, and prognostic factors of patients with penoscrotal invasive extramammary Paget's disease (EMPD).
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Intracellular microenvironment-responsive label-free autofluorescent nanogels for traceable gene delivery.
Adv Healthc Mater
PUBLISHED: 04-07-2014
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Gene therapy presents a unique opportunity for the treatment of genetic diseases, but the lack of multifunctional delivery systems has hindered its clinical applications. Here, a new delivery vector, autofluorescent polyethyleneimine (PEI) nanogels, for highly efficient and traceable gene delivery is developed. Different from commercial high-molecular-weight PEI, the cationic nanogels are noncytotoxic and able to be fragmented due to their unique intracellular microenvironment-responsive structures. The biodegradable nanogels can effectively load plasmid DNA (pDNA), and the self-assembled polyplexes can be cleaved after cellular uptake to improve gene transfection efficiency. Most importantly, the nanogels and the nanogel/pDNA polyplexes are autofluorescent. The fluorescence is stable in blood plasma and responsive to the intracellular microenvironment. The breakup of the nanogels or polyplexes leads to the loss of fluorescence, and thus the gene delivery and carrier biodegradation processes can be monitored. The reported multifunctional system demonstrates excellent biocompatibility, high transfection efficiency, responsive biodegradability, controlled gene release, label-free and simultaneous fluorescence tracking, which will provide a new platform for future scientific investigation and practical implications in gene therapy.
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Graphitic carbon nitride nanosheet-carbon nanotube three-dimensional porous composites as high-performance oxygen evolution electrocatalysts.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 04-02-2014
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A new class of highly efficient oxygen evolution catalysts has been synthesized through the self-assembly of graphitic carbon nitride nanosheets and carbon nanotubes, driven by ?-? stacking and electrostatic interactions. Remarkably, the catalysts exhibit higher catalytic oxygen evolution activity and stronger durability than Ir-based noble-metal catalysts and display the best performance among the reported nonmetal catalysts. This good result is attributed to the high nitrogen content and the efficient mass and charge transfer in the porous three-dimensional nanostructure.
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Hydrogen evolution by a metal-free electrocatalyst.
Nat Commun
PUBLISHED: 04-02-2014
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Electrocatalytic reduction of water to molecular hydrogen via the hydrogen evolution reaction may provide a sustainable energy supply for the future, but its commercial application is hampered by the use of precious platinum catalysts. All alternatives to platinum thus far are based on nonprecious metals, and, to our knowledge, there is no report about a catalyst for electrocatalytic hydrogen evolution beyond metals. Here we couple graphitic-carbon nitride with nitrogen-doped graphene to produce a metal-free hybrid catalyst, which shows an unexpected hydrogen evolution reaction activity with comparable overpotential and Tafel slope to some of well-developed metallic catalysts. Experimental observations in combination with density functional theory calculations reveal that its unusual electrocatalytic properties originate from an intrinsic chemical and electronic coupling that synergistically promotes the proton adsorption and reduction kinetics.
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New Biogeographic insight into Bauhinia s.l. (Leguminosae): integration from fossil records and molecular analyses.
BMC Evol. Biol.
PUBLISHED: 03-31-2014
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Given that most species that have ever existed on earth are extinct, it stands to reason that the evolutionary history can be better understood with fossil taxa. Bauhinia is a typical genus of pantropical intercontinental disjunction among the Asian, African, and American continents. Geographic distribution patterns are better recognized when fossil records and molecular sequences are combined in the analyses. Here, we describe a new macrofossil species of Bauhinia from the Upper Miocene Xiaolongtan Formation in Wenshan County, Southeast Yunnan, China, and elucidate the biogeographic significance through the analyses of molecules and fossils.
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Ectopic expression of B and T lymphocyte attenuator in gastric cancer: A potential independent prognostic factor in patients with gastric cancer.
Mol Med Rep
PUBLISHED: 03-19-2014
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It has been confirmed that B and T lymphocyte attenuator (BTLA; also known as CD272) is a novel co--inhibitory molecule that exhibits a critical role in restraining cell--mediated antitumor immunity. The present study aimed to investigate the expression and prognostic significance of BTLA in gastric adenocarcinoma. Immunohistochemical (IHC) staining was performed to investigate BTLA expression in gastric cancer tissues and normal mucosal tissues. In total, 123 pathologically confirmed specimens were obtained from stage IIIa gastric cancers. A correlation test, Kaplan-Meier curves, and a Cox proportional hazards regression model were used to analyze the data. No BTLA staining in the normal tissues was found, while BTLA-stained gastric carcinoma cells were detected in 75.6% (93/123) of the gastric cancer specimens. High expression levels of BTLA were detected in 31.7% (39/123) of the specimens, while low expression levels were detected in 68.3% (84/123) of the specimens. High BTLA expression levels were associated with shorter survival time, as confirmed by univariate and multivariate analyses. These findings provide a basis for the concept that high BTLA expression levels in gastric cancer, identified by IHC, are an independent biomarker for the poor prognosis of patients with gastric cancer.
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Origin of the electrocatalytic oxygen reduction activity of graphene-based catalysts: a roadmap to achieve the best performance.
J. Am. Chem. Soc.
PUBLISHED: 03-11-2014
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The mutually corroborated electrochemical measurements and density functional theory (DFT) calculations were used to uncover the origin of electrocatalytic activity of graphene-based electrocatalysts for oxygen reduction reaction (ORR). A series of graphenes doped with nonmetal elements was designed and synthesized, and their ORR performance was evaluated in terms of four electrochemical descriptors: exchange current density, on-set potential, reaction pathway selectivity and kinetic current density. It is shown that these descriptors are in good agreement with DFT calculations, allowing derivation of a volcano plot between the ORR activity and the adsorption free energy of intermediates on metal-free materials, similarly as in the case of metallic catalysts. The molecular orbital concept was used to justify this volcano plot, and to theoretically predict the ORR performance of an ideal graphene-based catalyst, the ORR activity of which is comparable to the state-of-the-art Pt catalyst. Moreover, this study may stimulate the development of metal-free electrocatalysts for other key energy conversion processes including hydrogen evolution and oxygen evolution reactions and largely expand the spectrum of catalysts for energy-related electrocatalysis reactions.
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Label-free dendrimer-like silica nanohybrids for traceable and controlled gene delivery.
Biomaterials
PUBLISHED: 02-27-2014
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To create advanced functional nanocarriers for achieving excellent gene delivery performance, fluorescence label-free hybridized dendrimer-like silica nanocarriers (HPSNs-AC-PEI) were developed by using the endosomal pH and cytoplasmic glutathione (GSH) responsive autofluorescent acetaldehyde-modified-cystine (AC) to link non-toxic low molecular weight branched polyethyleneimine (PEI) onto amino-functionalized dendrimer-like silica nanoparticles with hierarchical pores (HPSNs-NH2). The specific microstructure of this hybridized nanocarrier makes it not only show low cytotoxicity and high gene loading capability, but also display high gene transfection efficiency. The cleavage of disulfide bonds caused by GSH facilitates plasmid DNA (pDNA) release. Moreover, the pH and GSH controlled gene delivery profile can be real-time tracked using the autofluorescence of HPSNs-AC-PEI.
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Evolutionary interrogation of human biology in well-annotated genomic framework of rhesus macaque.
Mol. Biol. Evol.
PUBLISHED: 02-27-2014
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With genome sequence and composition highly analogous to human, rhesus macaque represents a unique reference for evolutionary studies of human biology. Here, we developed a comprehensive genomic framework of rhesus macaque, the RhesusBase2, for evolutionary interrogation of human genes and the associated regulations. A total of 1,667 next-generation sequencing (NGS) data sets were processed, integrated, and evaluated, generating 51.2 million new functional annotation records. With extensive NGS annotations, RhesusBase2 refined the fine-scale structures in 30% of the macaque Ensembl transcripts, reporting an accurate, up-to-date set of macaque gene models. On the basis of these annotations and accurate macaque gene models, we further developed an NGS-oriented Molecular Evolution Gateway to access and visualize macaque annotations in reference to human orthologous genes and associated regulations (www.rhesusbase.org/molEvo). We highlighted the application of this well-annotated genomic framework in generating hypothetical link of human-biased regulations to human-specific traits, by using mechanistic characterization of the DIEXF gene as an example that provides novel clues to the understanding of digestive system reduction in human evolution. On a global scale, we also identified a catalog of 9,295 human-biased regulatory events, which may represent novel elements that have a substantial impact on shaping human transcriptome and possibly underpin recent human phenotypic evolution. Taken together, we provide an NGS data-driven, information-rich framework that will broadly benefit genomics research in general and serves as an important resource for in-depth evolutionary studies of human biology.
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External validation of nomograms for predicting cancer-specific mortality in penile cancer patients treated with definitive surgery.
Chin J Cancer
PUBLISHED: 02-19-2014
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Using a population-based cancer registry, Thuret et al. developed 3 nomograms for estimating cancer-specific mortality in men with penile squamous cell carcinoma. In the initial cohort, only 23.0% of the patients were treated with inguinal lymphadenectomy and had pN stage. To generalize the prediction models in clinical practice, we evaluated the performance of the 3 nomograms in a series of penile cancer patients who were treated with definitive surgery. Clinicopathologic information was obtained from 160 M0 penile cancer patients who underwent primary tumor excision and regional lymphadenectomy between 1990 and 2008. The predicted probabilities of cancer-specific mortality were calculated from 3 nomograms that were based on different disease stage definitions and tumor grade. Discrimination, calibration, and clinical usefulness were assessed to compare model performance. The discrimination ability was similar in nomograms using the TNM classification or American Joint Committee on Cancer staging (Harrell's concordance index = 0.817 and 0.832, respectively), whereas it was inferior for the Surveillance, Epidemiology and End Results staging (Harrell's concordance index = 0.728). Better agreement with the observed cancer-specific mortality was shown for the model consisting of TNM classification and tumor grade, which also achieved favorable clinical net benefit, with a threshold probability in the range of 0 to 42%. The nomogram consisting of TNM classification and tumor grading was shown to have better performance for predicting cancer-specific mortality in penile cancer patients who underwent definitive surgery. Our data support the integration of this model in decision-making and trial design.
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A nomogram to predict Gleason sum upgrading of clinically diagnosed localized prostate cancer among Chinese patients.
Chin J Cancer
PUBLISHED: 02-14-2014
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Although several models have been developed to predict the probability of Gleason sum upgrading between biopsy and radical prostatectomy specimens, most of these models are restricted to prostate-specific antigen screening-detected prostate cancer. This study aimed to build a nomogram for the prediction of Gleason sum upgrading in clinically diagnosed prostate cancer. The study cohort comprised 269 Chinese prostate cancer patients who underwent prostate biopsy with a minimum of 10 cores and were subsequently treated with radical prostatectomy. Of all included patients, 220 (81.8%) were referred with clinical symptoms. The prostate-specific antigen level, primary and secondary biopsy Gleason scores, and clinical T category were used in a multivariate logistic regression model to predict the probability of Gleason sum upgrading. The developed nomogram was validated internally. Gleason sum upgrading was observed in 90 (33.5%) patients. Our nomogram showed a bootstrap-corrected concordance index of 0.789 and good calibration using 4 readily available variables. The nomogram also demonstrated satisfactory statistical performance for predicting significant upgrading. External validation of the nomogram published by Chun et al. in our cohort showed a marked discordance between the observed and predicted probabilities of Gleason sum upgrading. In summary, a new nomogram to predict Gleason sum upgrading in clinically diagnosed prostate cancer was developed, and it demonstrated good statistical performance upon internal validation.
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Elimination of central sleep apnea by cardiac valve replacement: a continuous follow-up study in patients with rheumatic valvular heart disease.
Sleep Med.
PUBLISHED: 02-10-2014
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Recent studies have suggested that cardiac surgery may affect sleep-disordered breathing (SDB) in chronic heart failure patients. However, the dynamic changes in sleep apnea and heart function after cardiac surgery and the mechanisms responsible for these changes remain unknown.
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Nitrogen and oxygen dual-doped carbon hydrogel film as a substrate-free electrode for highly efficient oxygen evolution reaction.
Adv. Mater. Weinheim
PUBLISHED: 02-08-2014
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A three-dimensional (3D) electrode composed of nitrogen, oxygen dualdoped graphene-carbon nanotube hydrogel film is fabricated, which greatly favors the transport and access of gas and reaction intermediates, and shows a remarkable oxygen-evolution catalytic performance in both alkaline and acidic solutions.
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Prognostic significance of the degree of extranodal extension in patients with penile carcinoma.
Asian J. Androl.
PUBLISHED: 02-01-2014
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This study sought to assess the prognostic significance of the degree of extranodal extension (ENE) and several other risk factors in pathological ENE penile carcinoma. We analyzed prospectively collected data on a consecutive series of 31 chemotherapy-naive patients with proven ENE who underwent therapeutic regional lymphadenectomy. Postoperative external radiotherapy was then performed. We studied the extent of ENE utilizing a novel grading system and correlated patient grades with their outcome measures. ENE was graded as 1 - if the capsule of the lymph node (LN) was ruptured less than one-third of its circumference or 2 - if the capsule was disrupted more than one-third of its circumference or the entire LN was disrupted. We estimated overall survival (OS) using the Kaplan-Meier method. Multivariate analysis was performed according to the Cox proportional hazards model using factors that were identified as statistically significant in univariate analysis. The incidence rate of ENE was 51.8% in patients with pathological node-positive carcinoma of the penis. The median OS and 5-year survival were 18 months (95% confidence interval (CI), 14.4-21.6) and 23%, respectively. Prognostic variables on univariate analysis were ENE grade 2, ? 3 LNs with ENE, maximal LN ? 35 mm, ? 5 positive LNs and pelvic LN involvement. On multivariate analysis, only ENE grade 2 remained associated with decreased OS (hazard ratio (HR): 6.50). In conclusion, patients with ENE have a poor outcome, and ENE grade 2 is an independent predictive factor of poor OS in patients with pathological ENE penile carcinoma.
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Long noncoding RNA expression signatures of bladder cancer revealed by microarray.
Oncol Lett
PUBLISHED: 01-31-2014
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Dysregulation of long noncoding RNAs (lncRNAs) has been regarded as a primary feature of several human cancers. However, the genome-wide expression and functional significance of lncRNAs in bladder cancer remains unclear. The aim of this study was to identify aberrantly expressed lncRNAs that may play an important role in contributing to bladder cancer pathogenesis. In this study, we described lncRNAs profiles in four pairs of human bladder cancer and matched normal bladder tissues by microarray. We finally determined 3,324 differentially expressed human lncRNAs and 2,120 differentially expressed mRNAs (?2-fold change). A total of 110 lncRNAs were significantly differentially expressed between the tumor and the control groups (?8-fold change). Four lncRNAs (TNXA, CTA-134P22.2, CTC-276P9.1 and KRT19P3) were selected for further confirmation of microarray results using quantitative PCR (qPCR), and a strong correlation was identified between the qPCR results and microarray data. We also observed that numerous lncRNA expression levels were significantly correlated with the expression of tens of protein coding genes by construction of the lncRNA-mRNA co-expression network. Kyoto Encyclopedia of Genes and Genomes annotation showed a significant association with p53, bladder cancer, cell cycle and propanoate metabolism pathway gene expression in the bladder cancer group compared with the normal tissue group, indicating that deregulated lncRNAs may act by regulating protein-coding genes in these pathways. We demonstrated the expression profiles of human lncRNAs in bladder cancer by microarray. We identified a collection of aberrantly expressed lncRNAs in bladder cancer compared with matched normal tissue. It is likely that these deregulated lncRNAs play a key or partial role in the development and/or progression of bladder cancer.
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Oral etoposide and oral prednisone for the treatment of castration resistant prostate cancer.
Kaohsiung J. Med. Sci.
PUBLISHED: 01-22-2014
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Treatment options for patients with castration-resistant prostate cancer (CRPC) are limited. The purpose of our study was to investigate the safety and efficacy in terms of prostate-specific antigen (PSA) response of a low-dose oral combination of etoposide and prednisone in patients with CRPC. Thirty-nine patients with prostate cancer (median age, 77.9 years) with progressive disease after standard hormonal therapy were enrolled. Etoposide (25 mg, twice daily) and prednisone (5 mg, twice daily) were administered orally. Each cycle comprised 21 consecutive days of treatment followed by a 7-day drug holiday. All patients previously treated with an antiandrogen were required to undergo antiandrogen withdrawal prior to entry into the study. A total of 226 cycles were administered with a median of 6.7 cycles per patient (range, 1-18 cycles). Sixteen of 39 patients (41%) with elevated PSA levels at baseline achieved at least a 50% reduction in PSA levels. Median progression-free survival for all patients was 5.9 months (range, 1-17 months). No Grade 4 toxicities were observed. The predominant toxicities were mucositis, nausea, fatigue, and anemia in twelve, nine, eight, and seven patients, respectively. Hematologic toxicity was infrequent, with no episodes of febrile neutropenia. The combination of low-dose etoposide and prednisone is an efficacious and reasonably well-tolerated oral regimen in the treatment of elderly patients with CRPC. This regimen can be easily administered in an outpatient setting and does not require frequent patient visits.
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Proton-functionalized two-dimensional graphitic carbon nitride nanosheet: an excellent metal-/label-free biosensing platform.
Small
PUBLISHED: 01-18-2014
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Ultrathin graphitic carbon nitride (g-C3N4) nanosheets, due to their interesting two-dimensional graphene-like structure and unique physicochemical properties, have attracted great research attention recently. Here, a new approach is developed to prepare, for the first time, proton-functionalized ultrathin g-C3N4 nanosheets by sonication-exfoliation of bulk g-C3N4 under an acid condition. This method not only reduces the exfoliation time from more than 10 h to 2 h, but also endows the nanosheets with positive charges. Besides retaining the properties of g-C3N4, the obtained nanosheets with the thickness of 2-4 nm (i.e., 6-12 atomic monolayers) also exhibit large specific surface area of 305 m(2) g(-1), enhanced fluorescence intensity, and excellent water dispersion stability due to their surface protonation and ultrathin morphology. The well-dispersed protonated g-C3N4 nanosheets are able to interact with negatively charged heparin, which results in the quenching of g-C3N4 fluorescence. A highly sensitive and highly selective heparin sensing platform based on protonated g-C3N4 nanosheets is established. This metal-free and fluorophore label-free system can reach the lowest heparin detection limit of 18 ng mL(-1).
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Freeze-drying of ovalbumin loaded mesoporous silica nanoparticle vaccine formulation increases antigen stability under ambient conditions.
Int J Pharm
PUBLISHED: 01-17-2014
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Amino functionalised mesoporous silica nanoparticles (AM-41) have been identified as a promising vaccine delivery material. The capacity of AM-41 to stabilise vaccine components at ambient temperature (23-27°C) was determined by adsorbing the model antigen ovalbumin (OVA) to AM-41 particles (OVA-41). The OVA-41 was successfully freeze-dried using the excipients 5% trehalose and 1% PEG8000. The immunological activity of OVA and the nanoparticle structure were maintained following two months storage at ambient temperature. The results of immunisation studies in mice with reconstituted OVA-41 demonstrated the induction of humoral and cell-meditated immune responses. The capacity of AM-41 particles to facilitate ambient storage of vaccine components without the loss of immunological potency will underpin the further development of this promising vaccine delivery platform.
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Earth-abundant cocatalysts for semiconductor-based photocatalytic water splitting.
Chem Soc Rev
PUBLISHED: 01-17-2014
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Photocatalytic water splitting represents a promising strategy for clean, low-cost, and environmental-friendly production of H2 by utilizing solar energy. There are three crucial steps for the photocatalytic water splitting reaction: solar light harvesting, charge separation and transportation, and the catalytic H2 and O2 evolution reactions. While significant achievement has been made in optimizing the first two steps in the photocatalytic process, much less efforts have been put into improving the efficiency of the third step, which demands the utilization of cocatalysts. To date, cocatalysts based on rare and expensive noble metals are still required for achieving reasonable activity in most semiconductor-based photocatalytic systems, which seriously restricts their large-scale application. Therefore, seeking cheap, earth-abundant and high-performance cocatalysts is indispensable to achieve cost-effective and highly efficient photocatalytic water splitting. This review for the first time summarizes all the developed earth-abundant cocatalysts for photocatalytic H2- and O2-production half reactions as well as overall water splitting. The roles and functional mechanism of the cocatalysts are discussed in detail. Finally, this review is concluded with a summary, and remarks on some challenges and perspectives in this emerging area of research.
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The HIF-2alpha dependent induction of PAP and adenosine synthesis regulates glioblastoma stem cell function through the A2B adenosine receptor.
Int. J. Biochem. Cell Biol.
PUBLISHED: 01-07-2014
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Glioblastomas are lethal tumors characterized by malignant proliferation and recurrence promoted partly by glioblastoma stem cells (GSCs). GSCs are known to be regulated by hypoxia, but the mechanisms involved in this regulation are not fully understood. We now demonstrate that hypoxia-inducible factor HIF2? and prostatic acid phosphatase (PAP) are preferentially expressed in hypoxic GSCs in comparison with non-stem tumor cells and normal neural stem cells and that PAP is regulated by HIF2?. Targeting PAP in hypoxic GSCs inhibits self-renewal and proliferation in vitro and attenuates tumor initiation potential of GSCs in vivo. Using specific adenosine receptor antagonists, we further find that the pro-proliferative role of PAP is stemmed from stimulated A2B adenosine receptors. Moreover, selective blockage of A2B receptor or knockdown of PAP or A2B on hypoxic GSCs results in significant reduction of phosphorylation of Akt and Erk-1/2. Our results demonstrate that PAP may play a pro-proliferative role in hypoxic GSCs with a HIF2?-induction pattern, which may be ascribed to stimulated A2B receptors and activated Akt and Erk-1/2 pathways. Therefore, we propose that these identified molecular regulators of GSCs in the hypoxic niche might represent promising targets for antiglioblastoma therapies.
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Electrophysiological phenotypes of MeCP2 A140V mutant mouse model.
CNS Neurosci Ther
PUBLISHED: 01-03-2014
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MeCP2 gene mutations are associated with Rett syndrome and X-linked mental retardation (XLMR), diseases characterized by abnormal brain development and function. Recently, we created a novel MeCP2 A140V mutation mouse model that exhibited abnormalities of cell packing density and dendritic branching consistent with that seen in Rett syndrome patients as well as other MeCP2 mutant mouse models. Therefore, we hypothesized that some deficits of neuronal and synaptic functions might also be present in the A140V mutant model.
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Interaction between HIV-1 Tat and DNA-PKcs modulates HIV transcription and class switch recombination.
Int. J. Biol. Sci.
PUBLISHED: 01-01-2014
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HIV-1 tat targets a variety of host cell proteins to facilitate viral transcription and disrupts host cellular immunity by inducing lymphocyte apoptosis, but whether it influences humoral immunity remains unclear. Previously, our group demonstrated that tat depresses expression of DNA-PKcs, a critical component of the non-homologous end joining pathway (NHEJ) of DNA double-strand breaks repair, immunoglobulin class switch recombination (CSR) and V(D)J recombination, and sensitizes cells to ionizing radiation. In this study, we demonstrated that HIV-1 Tat down-regulates DNA-PKcs expression by directly binding to the core promoter sequence. In addition, Tat interacts with and activates the kinase activity of DNA-PKcs in a dose-dependent and DNA independent manner. Furthermore, Tat inhibits class switch recombination (CSR) at low concentrations (?4 µg/ml) and stimulates CSR at high concentrations (?8 µg/ml). On the other hand, low protein level and high kinase activity of DNA-PKcs promotes HIV-1 transcription, while high protein level and low kinase activity inhibit HIV-1 transcription. Co-immunoprecipitation results revealed that DNA-PKcs forms a large complex comprised of Cyclin T1, CDK9 and Tat via direct interacting with CDK9 and Tat but not Cyclin T1. Taken together, our results provide new clues that Tat regulates host humoral immunity via both transcriptional depression and kinase activation of DNA-PKcs. We also raise the possibility that inhibitors and interventions directed towards DNA-PKcs may inhibit HIV-1 transcription in AIDS patients.
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[Exploratory analysis of the effect of toxicity of sunitinib on the clinical outcome of patients with advanced renal cell carcinoma].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 12-31-2013
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To explore the effect of toxicity of sunitinib on the clinical outcome of patients with advanced renal cell carcinoma (RCC) .
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Hierarchically Porous Nitrogen-Doped Graphene-NiCo2O4 Hybrid Paper as an Advanced Electrocatalytic Water-Splitting Material.
ACS Nano
PUBLISHED: 10-07-2013
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In this work, we report a three-dimensional (3D) oxygen evolution reaction (OER) catalyst with hierarchical pores for water splitting. The remarkable features of well-developed in- and out-of-plane pores, 3D conductive networks, and N-doping have greatly promoted the transport in electrodes and assured high catalytic efficiency. The 3D hybrid paper of N-doped graphene-NiCo2O4 has shown a remarkable OER catalytic activity that was comparable to that of previously reported noble metal catalysts (IrO2). The catalytic process occurred with favorable kinetics and strong durability. The dual-active-site mechanism is responsible for the excellent performance of the hybrid catalyst; that is, the edges of NiCo2O4 and the N (O)-metal (Ni or Co) bonds are both active sites. This study affords a new strategy to achieve optimal performance in 3D catalysts, which may be extended to the preparation of other 3D hybrid materials for a broad range of technological applications.
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Ordered Mesoporous Core/Shell SnO2 /C Nanocomposite as High-Capacity Anode Material for Lithium-Ion Batteries.
Chemistry
PUBLISHED: 08-29-2013
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High on energy: An ordered mesoporous core/shell structured SnO2 /C nanocomposite was obtained from a facile vacuum-assisted impregnation route by using SBA-15 as a hard template. The nanocomposoite exhibits high specific capacity and excellent high-rate performance as an anode material for lithium-ion battery.
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Prevalence and risk factors of sleep disordered breathing in patients with rheumatic valvular heart disease.
J Clin Sleep Med
PUBLISHED: 08-16-2013
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Sleep disordered breathing (SDB) is common in patients with chronic heart failure secondary to non-valvular heart disease; however, the prevalence and characteristics of SDB in patients with rheumatic valvular heart disease (RVHD) are unclear. This study was designed to determine the prevalence, characteristics, and risk factors for SDB in RVHD patients.
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Intracellular Microenvironment Responsive Polymers: A Multiple-stage Transport Platform for High-Performance Gene Delivery.
Small
PUBLISHED: 08-08-2013
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A new strategy for promoting endoplasmic gene delivery and nucleus uptake is proposed by developing intracellular microenvironment responsive biocompatible polymers. This delivery system can efficiently load and self-assemble nucleic acids into nano-structured polyplexes at a neutral pH, release smaller imidazole-gene complexes from the polymer backbones at intracellular endosomal pH, transport nucleic acids into nucleus through intracellular environment responsive multiple-stage gene delivery, thus leading to a high cell transfection efficiency.
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[Hematologic adverse effects in patients with renal cell carcinoma treated with sunitinib].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 07-19-2013
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To explore the hematologic adverse effects in patients with renal cell carcinoma treated with sunitinib.
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Three-Dimensional N-Doped Graphene Hydrogel/NiCo Double Hydroxide Electrocatalysts for Highly Efficient Oxygen Evolution.
Angew. Chem. Int. Ed. Engl.
PUBLISHED: 07-16-2013
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A highly hydrated structure was fabricated for catalyzing the oxygen evolution reaction (OER), which demonstrated significantly enhanced catalytic activity, favorable kinetics, and strong durability. The enhanced performance is correlated with the dual-active-site mechanism, and high hydrophilicity of the electrode can dramatically expedite the process of water oxidation into molecular oxygen.
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?H2AX foci formation in the absence of DNA damage: mitotic H2AX phosphorylation is mediated by the DNA-PKcs/CHK2 pathway.
FEBS Lett.
PUBLISHED: 06-11-2013
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Phosphorylated H2AX is considered to be a biomarker for DNA double-strand breaks (DSB), but recent evidence suggests that ?H2AX does not always indicate the presence of DSB. Here we demonstrate the bimodal dynamic of H2AX phosphorylation induced by ionizing radiation, with the second peak appearing when G2/M arrest is induced. An increased level of ?H2AX occurred in mitotic cells, and this increase was attenuated by DNA-PKcs inactivation or Chk2 depletion, but not by ATM inhibition. The phosphorylation-mimic CHK2-T68D abrogated the attenuation of mitotic ?H2AX induced by DNA-PKcs inactivation. Thus, the DNA-PKcs/CHK2 pathway mediates the mitotic phosphorylation of H2AX in the absence of DNA damage.
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N-doped graphene natively grown on hierarchical ordered porous carbon for enhanced oxygen reduction.
Adv. Mater. Weinheim
PUBLISHED: 06-05-2013
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A novel nitrogen doped hybrid material composed of in situ-formed graphene natively grown on hierarchical ordered porous carbon is prepared, which successfully combines the advantages of both materials, such as high surface area, high mass transfer, and high conductivity. The outstanding structural properties of the resultant material render it an excellent metal-free catalyst for electrochemical oxygen reduction.
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Influence of obesity on localized prostate cancer patients treated with radical prostatectomy.
Asian J. Androl.
PUBLISHED: 06-03-2013
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This study aimed to investigate the association between different anthropometric measures of obesity and clinicopathological characteristics in Chinese patients with clinically localized prostate cancer (PCa). A total of 734 patients with clinically localized PCa who underwent radical prostatectomy (RP) were included in this study. Clinical and pathological data from each patient were collected. Anthropometric measures of abdominal adiposity were measured from T2-weighted sagittal localisation images from magnetic resonance imaging (MRI) for 413 (56.3%) patients. Patient clinical and pathological characteristics were compared across body mass index (BMI) groups. Univariable and multivariable logistic regression models were used to address the influence of the preoperative total testosterone level and anthropometric measures of obesity on pathological outcomes. In the multivariate analysis, BMI was not significantly associated with any pathological outcomes. However, the percentage of visceral adipose tissue (VAT%) was an independent predictor of a pathological Gleason score ?8 (P<0.001), extracapsular extension (ECE; P=0.002) and seminal vesicle invasion (SVI; P=0.007). More importantly, we found that the preoperative total testosterone level was significantly correlated with the VAT% (Pearsons correlation coefficient: -0.485, P<0.001) and subcutaneous adipose tissue (SAT; Pearsons correlation coefficient: 0.413, P<0.001). In conclusion, the results of this study suggest that abdominal fat distribution, and particularly VAT%, is associated with a risk of advanced PCa. Moreover, our present study confirms a significant inverse correlation between visceral adiposity and testosterone. Further studies are warranted to elucidate the biological mechanisms underlying the relationship between abdominal adiposity and the aggressiveness of PCa.
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Developing Functionalized Dendrimer-Like Silica Nanoparticles with Hierarchical Pores as Advanced Delivery Nanocarriers.
Adv. Mater. Weinheim
PUBLISHED: 05-14-2013
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Functionalized dendrimer-like hybrid silica nanoparticles with hierarchical pores are designed and synthesized. The unique structure, large surface area, and excellent biocompability render such materials attractive nanocarriers for the advanced delivery of various sized drugs and genes simultaneously.
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Enhanced visible-light hydrogen-production activity of copper-modified ZnxCd(1-x)S.
ChemSusChem
PUBLISHED: 04-30-2013
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Copper modification is an efficient way to enhance the photocatalytic activity of ZnS-based materials; however, the mechanisms of Cu(2+) surface and bulk modifications for improving the activity are quite different. In this work, two different synthetic pathways were devised to prepare surface and bulk Cu(2+)-modified Znx Cd1-x S photocatalysts through cation-exchange and coprecipitation methods, respectively. Different Cu(2+) modifications brought different effects on the phase structure, morphology, surface area, optical property, as well as the photocatalytic H2-production activity of the final products. The optimized Cu(2+)-surface-modified Znx Cd1-x S photocatalyst has a high H2-production rate of 4638.5 ?molh(-1) g(-1) and an apparent quantum efficiency of 20.9% at 420 nm, exceeding that of Cu(2+)-bulk-modified catalyst at the same copper content. Cu(2+) surface modification not only brings a new electron-transferring pathway (interfacial charge transfer), but also produces new surface active sites for H2 evolution, reducing the recombination rate of photogenerated charge carriers.
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Fabrication of NiS modified CdS nanorod p-n junction photocatalysts with enhanced visible-light photocatalytic H2-production activity.
Phys Chem Chem Phys
PUBLISHED: 04-19-2013
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Production of hydrogen from photocatalytic water splitting has become an attractive research area due to the possibility of converting solar energy into green chemical energy. In this study, novel NiS nanoparticle (NP) modified CdS nanorod (NR) p-n junction photocatalysts were prepared by a simple two-step hydrothermal method. Even without the Pt co-catalyst, the as-prepared NiS NP-CdS NR samples exhibited enhanced visible-light photocatalytic activity and good stability for H2-production. The optimal NiS loading content was determined to be 5 mol%, and the corresponding H2-production rate reached 1131 ?mol h(-1) g(-1), which is even higher than that of the optimized Pt-CdS NRs. It is believed that the assembly of p-type NiS NPs on the surface of n-type CdS NRs could form a large number of p-n junctions, which could effectively reduce the recombination rates of electrons and holes, thus greatly enhancing the photocatalytic activity. This work not only shows a possibility for the utilization of low cost NiS nanoparticles as a substitute for noble metals (such as Pt) in the photocatalytic H2-production but also provides a new insight into the design and fabrication of other new p-n junction photocatalysts for enhancing H2-production activity.
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[Necessity analysis of bone scan in patients with newly diagnosed prostate cancer].
Zhonghua Yi Xue Za Zhi
PUBLISHED: 04-13-2013
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To construct a classification and regression tree (CART) to predict the occurrences of bone metastases in patients with newly diagnosed prostate cancer so as to reduce unnecessary bone scans.
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Clinicopathologic significance of putative stem cell marker, CD44 and CD133, in human gastric carcinoma.
J Surg Oncol
PUBLISHED: 03-06-2013
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CD44 and CD133 have been reported as putative stem cell markers. However, the clinicopathologic significance of CD44 and CD133 expression in patients with gastric carcinoma (GC) has not been clearly elucidated.
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Defining good candidates for extraperitoneal cystectomy: results from random peritoneum biopsies of 136 cases.
Urology
PUBLISHED: 02-20-2013
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To define who are good candidates for extraperitoneal cystectomy.
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Identification of anaplastic lymphoma kinase break points and oncogenic mutation profiles in acral/mucosal melanomas.
Pigment Cell Melanoma Res
PUBLISHED: 02-19-2013
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Acral and mucosal melanomas, the two most common subtypes of melanoma in China, exhibit different genetic alterations and biologic behavior compared with other subtypes of melanomas. The purpose of this study was to identify the genetic alterations in patients with acral or mucosal melanomas in southern China. Fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) analysis, polymerase chain reaction (PCR), and quantitative real-time reverse transcriptase PCR (qRT-PCR) were used to assess the anaplastic lymphoma kinase (ALK) break points. Furthermore, a mass spectrometry-based genotyping platform was used to analyze 30 acral melanomas and 28 mucosal melanomas to profile 238 known somatic mutations in 19 oncogenes. ALK break points were identified in four acral cases (6.9%). Eight (13.8%) cases harbored BRAF mutations, six (10.3%) had NRAS mutations, four (6.9%) had KIT mutations, two (3.5%) had EGFR mutations, two (3.5%) had KRAS mutations, two (3.5%) had MET mutations, one (1.7%) had an HRAS mutation, and one (1.7%) had a PIK3CA mutation. Two cases exhibited co-occurring mutations, and one case with a BRAF mutation had a translocation in ALK. This study represents a comprehensive and concurrent analysis of the major recurrent oncogenic mutations involved in melanoma cases from southern China. These data have implications for both clinical trial designs and therapeutic strategies.
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The prognostic value of platelet endothelial cell adhesion molecule-1 in non-small-cell lung cancer patients.
Med. Oncol.
PUBLISHED: 02-18-2013
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Our previous studies have shown that platelet endothelial cell adhesion molecule-1 (PECAM-1), a member of the immunoglobulin superfamily, is a critical mediator of anchorage-independent growth and anoikis resistance in lung carcinoma cells. The purpose of this study was to analyze the protein expression of PECAM-1 in non-small-cell lung carcinoma (NSCLC) tissues and its clinical significance in NSCLC patients. By immunohistochemical analysis, high microvessel density (MVD) of PECAM-1 was detected in the stromal tissues of NSCLC. The MVD of PECAM-1 was strongly correlated with the N stage (p = 0.029), M stage (p = 0.001) and clinical stage (p = 0.001) of NSCLC patients. Survival analysis revealed high MVD of PECAM-1 in both primary NSCLC lesions and metastatic lymph node tissues, and these results were found to be significantly correlated with poor overall survival in NSCLC patients (p < 0.001 and p = 0.021, respectively). Moreover, patients with high PECAM-1 MVD had worse overall survival in either adenocarcinoma or EGFR mutation subgroups. Multivariate analysis revealed that the MVD of PECAM-1 was an independent prognostic factor for NSCLC patients. The MVD of PECAM-1 is also a potential predictor for NSCLC patients treated with first-line platinum-based doublet chemotherapy, as high PECAM-1 MVD correlated with worse overall survival. Our results demonstrated that MVD of PECAM-1 could be a potential prognostic factor and therapeutic target in NSCLC.
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Pseudomonas aeruginosa-mannose-sensitive hemagglutinin inhibits proliferation and induces apoptosis in a caspase-dependent manner in human bladder cancer cell lines.
Oncol Lett
PUBLISHED: 02-14-2013
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The aim of the present study was to investigate the effects of Pseudomonas aeruginosa-mannose-sensitive hemagglutinin (PA-MSHA) on inhibiting the proliferation of bladder cancer cell lines and to further define its functional mechanisms. T24 and 5637 cells were treated with PA-MSHA at various concentrations and times. Cell proliferation was analyzed using Cell Counting Kit-8 (CCK-8) assays. The cell cycle distribution and apoptosis induced by PA-MSHA were measured by flow cytometry with propidium iodide (PI) and annexin V-fluorescein isothiocyanate (FITC) staining. Western blotting was used to evaluate the expression levels of the apoptosis-related molecules and PI3K-AKT-mTOR signaling pathway proteins. A time- and concentration-dependent cytotoxic effect of PA-MSHA was observed in the T24 and 5637 cells. Flow cytometry with PI and annexin V-FITC staining showed that the various concentrations of PA-MSHA were all able to induce the apoptosis and G0-G1 cell cycle arrest of the bladder cancer cells. Cleaved caspase-8 and -9 and Fas protein expression levels were markedly associated with an increase in the apoptosis of the bladder cancer cells. The cells stimulated with PA-MSHA also exhibited a downregulation of PI3K-AKT-mTOR signaling. PA-MSHA inhibits proliferation and induces apoptosis in the T24 and 5637 bladder cancer cell lines by modulating caspase family proteins and affecting the cell cycle regulation machinery. The PI3K-AKT-mTOR signaling pathway may be important in the direct anticancer cytotoxic effect of PA-MSHA.
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The effectiveness of the TAX 327 nomogram in predicting overall survival in Chinese patients with metastatic castration-resistant prostate cancer.
Asian J. Androl.
PUBLISHED: 02-06-2013
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Based on the results of TAX 327, a nomogram was developed to predict the overall survival of metastatic castration-resistant prostate cancer (mCRPC) after first-line chemotherapy. The nomogram, however, has not been validated in an independent dataset, especially in a series out of clinical trials. Thus, the objective of the current study was to validate the TAX 327 nomogram in a community setting in China. A total of 146 patients with mCRPC who received first-line chemotherapy (docetaxel or mitoxantrone) were identified. Because clinical trials are limited in mainland China, those patients did not receive investigational treatment after the failure of first-line chemotherapy. The predicted overall survival rate was calculated from the TAX 327 nomogram. The validity of the model was assessed with discrimination, calibration and decision curve analysis. The median survival of the cohort was 21 months (docetaxel) and 19 months (mitoxantrone) at last follow-up. The predictive c-index of the TAX 327 nomogram was 0.66 (95% CI: 0.54-0.70). The calibration plot demonstrated that the 2-year survival rate was underestimated by the nomogram. Decision curve analysis showed a net benefit of the nomogram at a threshold probability greater than 30%. In conclusion, the present validation study did not confirm the predictive value of the TAX 327 nomogram in a contemporary community series of men in China, and further studies with a large sample size to develop or validate nomograms for predicting survival and selecting therapies in advanced prostate cancer are necessary.
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An elevated serum miR-141 level in patients with bone-metastatic prostate cancer is correlated with more bone lesions.
Asian J. Androl.
PUBLISHED: 02-04-2013
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The skeleton is the most common metastatic organ in patients with prostate cancer (PCa). Non-invasive biomarkers that can facilitate the detection and monitoring of bone metastases are highly desirable. We designed this study to assess the expression patterns of serum miR-141 in patients with bone-metastatic PCa. Serum samples were collected to measure the miR-141 level in 56 patients, including six with benign prostatic hyperplasia (BPH), 20 with localized PCa and 30 with bone-metastatic PCa (10 with hormone-naive PCa, 10 with hormone-sensitive PCa and 10 with hormone-refractory PCa). A bone scan was performed for each patient with PCa to assess the number of bone lesions. The quantification of serum miR-141 levels was assayed by specific TaqMan qRT-PCR. The results showed that serum miR-141 levels were elevated in patients with bone metastasis (P<0.001). There was no statistically significant difference in the serum miR-141 levels between patients with BPH and patients with localized PCa. Using Kendalls bivariate correlation test, both the Gleason score and the number of bone-metastatic lesions were found to correlate with serum miR-141 levels (P=0.012 and P<0.001, respectively). The serum miR-141 level was found to be positively correlated with alkaline phosphatase (ALP) level in patients with skeletal metastasis, using Pearsons bivariate correlation test. No relationship was found between the serum miR-141 level and the serum prostate-specific antigen (PSA) level. We concluded that serum miR-141 levels are elevated in patients with bone-metastatic PCa and that patients with higher levels of serum miR-141 developed more bone lesions. Furthermore, serum miR-141 levels are correlated with serum ALP levels but not serum PSA levels.
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Kinetics of testosterone recovery in clinically localized prostate cancer patients treated with radical prostatectomy and subsequent short-term adjuvant androgen deprivation therapy.
Asian J. Androl.
PUBLISHED: 01-22-2013
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Androgen deprivation therapy (ADT) is a standard treatment for metastatic, recurrent and locally advanced prostate cancer (PCa). The aim of this study is to investigate the timing and extent of testosterone recovery in clinically localized PCa patients treated with radical prostatectomy (RP) and subsequent short-term adjuvant ADT. A total of 95 localized PCa patients underwent RP and 9-month adjuvant ADT were included in this prospective study. Serum testosterone level was measured before adjuvant ADT, at ADT cessation, and at 1, 3, 6, 9 and 12 months after cessation of ADT. A Cox proportional hazards model was used to assess variables associated with the time of testosterone normalization. The results showed that median patient age was 67 years and median testosterone level before adjuvant ADT was 361 (230-905) ng dl(-1). All patients finished 9-month adjuvant ADT and achieved castrate testosterone level. At 3 months after ADT cessation, testosterone recovered to supracastrate level in 97.9% patients and to normal level in 36.9% patients. The percentage of patients who recovered to normal testosterone level increased to 66.3%, 86.3% and 92.6% at 6, 9 and 12 months, respectively. Cox regression model found that higher baseline testosterone level (? 300 ng dl(-1)) was the only variable associated with a shorter time to testosterone normalization (hazard ratio: 1.98; P = 0.012). In conclusion, in most patients, testosterone recovered to supracastrate level at 3 months and to normal level at 12 months after 9-month adjuvant ADT cessation. Patients with higher baseline testosterone level need shorter time of testosterone normalization.
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Time-varying pattern of recurrence risk for gastric cancer patients.
Med. Oncol.
PUBLISHED: 01-18-2013
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This study analyzed the time-varying pattern of the recurrence risk for gastric cancer after surgery. A total of 1,222 gastric patients undergoing D2 resection surgery were studied retrospectively. The annual recurrence hazard curve for all of the populations showed one early peak and a late rise within 10 years after the surgery. The first major recurrence peak covers the first 3 years after the surgery, rising to a maximum at 1.5 years after surgery, followed by a decline until 7.5 years after the surgery, at which point the curve began to rise again. A subgroup analysis of this pattern also revealed that the curves of the patients with bigger tumors, poorly differentiated/undifferentiated adenocarcinomas, lymphatic/venous invasion, T3 and T4, node positive or with fewer lymph nodes retrieved were steeper. Chemotherapy can reduce the hazard rate for recurrence of gastric cancer. Our study confirms the time-varying pattern of the recurrence risk for gastric cancer, and it further supports the hypothesis of tumor dormancy after surgery. To effectively reduce the recurrence risk, new adjuvant therapies beyond chemotherapy may be needed.
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Comparison of three versions of partin tables to predict final pathologic stage in a chinese cohort: a decision curve analysis.
Urol. Int.
PUBLISHED: 01-17-2013
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To compare Partin tables (PTs) 1997, 2001, and 2007 for their clinical applicability in a Chinese cohort based upon a decision curve analysis (DCA).
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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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