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Find video protocols related to scientific articles indexed in Pubmed.
Effect of deoxycholic acid on Ca(2+) movement, cell viability and apoptosis in human gastric cancer cells.
Toxicol. Mech. Methods
PUBLISHED: 11-20-2014
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Abstract Deoxycholic acid (DOA) is one of the secondary bile acids used as a mild detergent for the isolation of membrane associated proteins. This study examined whether the secondary bile acid, DOA, altered Ca(2+) movement, cell viability and apoptosis in SCM1 human gastric cancer cells. The Ca(2+)-sensitive fluorescent dye fura-2 was used to measure [Ca(2+)]i. DOA evoked [Ca(2+)]i rises concentration-dependently. The response was reduced by removing extracellular Ca(2+). DOA-evoked Ca(2+) entry was inhibited by store-operated Ca(2+) channel inhibitors (nifedipine, econazole and SKF96365), the protein kinase C (PKC) activator phorbol 12-myristate 13 acetate (PMA) and the PKC inhibitor GF109203X. In Ca(2+)-free medium, treatment with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) abolished DOA-evoked [Ca(2+)]i rises. Conversely, treatment with DOA abolished TG-evoked [Ca(2+)]i rises. Inhibition of phospholipase C with U73122 abolished DOA-evoked [Ca(2+)]i rises. At 100-500 ?M, DOA decreased cell viability, which was not changed by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM). DOA between 100 ?M and 300 ?M also induced apoptosis. Collectively, in SCM1 cells, DOA induced [Ca(2+)]i rises by evoking phospholipase C-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via store-operated Ca(2+) channels. DOA also caused Ca(2+)-independent apoptosis.
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Distinct aetiopathogenesis in subgroups of functional dyspepsia according to the Rome III criteria.
Gut
PUBLISHED: 11-20-2014
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Whether there is distinct pathogenesis in subgroups of functional dyspepsia (FD), the postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS) remains controversial. We aimed to identify the risk factors of FD and its subgroups in the Chinese population.
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How to make a cardiomyocyte.
Development
PUBLISHED: 11-18-2014
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During development, cardiogenesis is orchestrated by a family of heart progenitors that build distinct regions of the heart. Each region contains diverse cell types that assemble to form the complex structures of the individual cardiac compartments. Cardiomyocytes are the main cell type found in the heart and ensure contraction of the chambers and efficient blood flow throughout the body. Injury to the cardiac muscle often leads to heart failure due to the loss of a large number of cardiomyocytes and its limited intrinsic capacity to regenerate the damaged tissue, making it one of the leading causes of morbidity and mortality worldwide. In this Primer we discuss how insights into the molecular and cellular framework underlying cardiac development can be used to guide the in vitro specification of cardiomyocytes, whether by directed differentiation of pluripotent stem cells or via direct lineage conversion. Additional strategies to generate cardiomyocytes in situ, such as reactivation of endogenous cardiac progenitors and induction of cardiomyocyte proliferation, will also be discussed.
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Osteoporosis increases subsequent risk of gallstone: a nationwide population-based cohort study in Taiwan.
BMC Gastroenterol
PUBLISHED: 11-18-2014
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BackgroundOsteopontin (OPN) is a pro-inflammatory cytokine which is expressed in various tissues. It participates in the bone remodeling process and stimulates bone resorption by osteoclasts. It is also a core protein of cholesterol gallstones. We hypothesized osteoporotic patients might have higher risk in developing gallstones and conducted a population-based study to examine the risk of developing gallstone in osteoporotic patients in Taiwan.MethodsA total of 1,638 patients diagnosed with osteoporosis between 2003 and 2005 were identified in the National Health Insurance Research Database. A comparison cohort without osteoporosis (n =6,552) was randomly matched to each osteoporosis patient at a ratio of 4: 1 based on age and sex. A Cox proportional-hazards regression analysis was performed to evaluate the 5-year gallstone-free survival rates for the 2 cohorts.ResultsDuring the 5-year follow-up period, 114 and 311 cases of gallstone occurred in the osteoporosis and comparison cohorts, respectively. After adjusting for the confounders, the Cox regression analysis of the risk of gallstone in the osteoporosis and comparison cohorts yielded a hazard ratio of 1.35 (95% confidence interval: 1.07 - 1.69; p < 0 .01).ConclusionPatients with osteoporosis in Taiwan have a higher risk of developing gallstone than the general population.
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Near-infrared photonic band structure in a semiconductor metamaterial photonic crystal.
Appl Opt
PUBLISHED: 11-18-2014
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In this study, we theoretically investigate the near-infrared (NIR) photonic band structure (PBS) in a one-dimensional semiconductor metamaterial (MM) photonic crystal (PC). The considered PC is (AB)N, where N is the stack number, A is a dielectric, and B is a semiconductor MM composed of Al-doped ZnO and ZnO. It is found that the photonic band gaps (PBGs) can be tunable by the variations in filling factor, and thicknesses of A and B. It is of particular interest to see that the PBG will vanish when the thicknesses of A and B satisfy a certain condition. The results provide fundamental information on a NIR PBS that could be of technical use in photonic applications using such a semiconductor MM. The band gap vanishing makes it possible to design a wider band pass filter at NIR based on the use of such a PC.
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Dendritic cells respond to nasopharygeal carcinoma cells through annexin A2-recognizing DC-SIGN.
Oncotarget
PUBLISHED: 11-06-2014
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Dendritic cells (DCs) play an essential role in immunity and are used in cancer immunotherapy. However, these cells can be tuned by tumors with immunosuppressive responses. DC-specific intercellular adhesion molecule 3-Grabbing Nonintegrin (DC-SIGN), a C-type lectin expressed on DCs, recognizes certain carbohydrate structures which can be found on cancer cells. Nasopharyngeal carcinoma (NPC) is an epithelial cell-derived malignant tumor, in which immune response remains unclear. This research is to reveal the molecular link on NPC cells that induces the immunosuppressive responses in DCs. In this article, we report identification of annexin A2 (ANXA2) on NPC cells as a ligand for DC-SIGN on DCs. N-linked mannose-rich glycan on ANXA2 may mediate the interaction. ANXA2 was abundantly expressed in NPC, and knockdown of ANXA2 suppressed NPC xenograft in mice, suggesting a crucial role of ANXA2 in NPC growth. Interaction with NPC cells caused DC-SIGN activation in DCs. Consequently DC maturation and the proinflammatory interleukin (IL)-12 production were inhibited, and the immunosuppressive IL-10 production was promoted. Blockage of either DC-SIGN or ANXA2 eliminated the production of IL-10 from DCs. This report suggests that suppression of ANXA2 at its expression or glycosylation on NPC may improve DC-mediated immunotherapy for the tumor.
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Design of multichannel filters based on the use of periodic Cantor dielectric multilayers.
Appl Opt
PUBLISHED: 10-17-2014
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A fractal multilayer structure made of two dielectric materials can exhibit photonic bandgap (PBG). In this work, with the use of this PBG, we study the transmission properties of periodic triadic Cantor set structures. The results indicate that the structure can be used to design multichannel filters with channel number equal to N-1 for a given number of periods, N. In addition, the channel frequencies can be designed at will. The considered structure provides another new type of design for a tunable multichannel filter.
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Synthetic Chemically Modified mRNA (modRNA): Toward a New Technology Platform for Cardiovascular Biology and Medicine.
Cold Spring Harb Perspect Med
PUBLISHED: 10-11-2014
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Over the past two decades, a host of new molecular pathways have been uncovered that guide mammalian heart development and disease. The ability to genetically manipulate these pathways in vivo have largely been dependent on the generation of genetically engineered mouse model systems or the transfer of exogenous genes in a variety of DNA vectors (plasmid, adenoviral, adeno-associated viruses, antisense oligonucleotides, etc.). Recently, a new approach to manipulate the gene program of the adult mammalian heart has been reported that will quickly allow the high-efficiency expression of virtually any protein in the intact heart of mouse, rat, porcine, nonhuman primate, and human heart cells via the generation of chemically modified mRNA (modRNA). The technology platform has important implications for delineating the specific paracrine cues that drive human cardiogenesis, and the pathways that might trigger heart regeneration via the rapid generation of modRNA libraries of paracrine factors for direct in vivo administration. In addition, the strategy can be extended to a variety of other cardiovascular tissues and solid organs across multiple species, and recent improvements in the core technology have supported moving toward the first human studies of modRNA in the next 2 years. These recent advances are reviewed along with projections of the potential impact of the technology for a host of other biomedical problems in the cardiovascular system.
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Next-Generation Models of Human Cardiogenesis via Genome Editing.
Cold Spring Harb Perspect Med
PUBLISHED: 09-20-2014
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Cardiogenesis is one of the earliest and most important steps during human development and is orchestrated by discrete families of heart progenitors, which build distinct regions of the fetal heart. For the past decade, a lineage map for the distinct subsets of progenitors that generate the embryonic mammalian heart has begun to lay a foundation for the development of new strategies for rebuilding the adult heart after injury, an unmet clinical need for the vast majority of patients with end-stage heart failure who are not heart transplant recipients. The studies also have implications for the root causes of congenital heart disease, which affects 1 in 50 live births, the most prevalent malformations in children. Although much of this insight has been generated in murine models, it is becoming increasingly clear that there can be important divergence with principles and pathways for human cardiogenesis, as well as for regenerative pathways. The development of human stem cell models, coupled with recent advances in genome editing with RNA-guided endonucleases, offer a new approach for the primary study of human cardiogenesis. In addition, application of the technology to the in vivo setting in large animal models, including nonhuman primates, has opened the door to genome-edited large animal models of adult and congenital heart disease, as well as a detailed mechanistic dissection of the more diverse and complex set of progenitor families and pathways, which guide human cardiogenesis. Implications of this new technology for a new generation of human-based, genetically tractable systems are discussed, along with potential therapeutic applications.
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Alveolar bone preservation subsequent to miniscrew implant placement in a canine model.
Orthod Craniofac Res
PUBLISHED: 09-11-2014
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To assess the effects of transcortical screws on alveolar (bone) ridge preservation following extraction.
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Improved assemblies using a source-agnostic pipeline for MetaGenomic Assembly by Merging (MeGAMerge) of contigs.
Sci Rep
PUBLISHED: 08-27-2014
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Assembly of metagenomic samples is a very complex process, with algorithms designed to address sequencing platform-specific issues, (read length, data volume, and/or community complexity), while also faced with genomes that differ greatly in nucleotide compositional biases and in abundance. To address these issues, we have developed a post-assembly process: MetaGenomic Assembly by Merging (MeGAMerge). We compare this process to the performance of several assemblers, using both real, and in-silico generated samples of different community composition and complexity. MeGAMerge consistently outperforms individual assembly methods, producing larger contigs with an increased number of predicted genes, without replication of data. MeGAMerge contigs are supported by read mapping and contig alignment data, when using synthetically-derived and real metagenomic data, as well as by gene prediction analyses and similarity searches. MeGAMerge is a flexible method that generates improved metagenome assemblies, with the ability to accommodate upcoming sequencing platforms, as well as present and future assembly algorithms.
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Design of Portable Mass Spectrometers with Handheld Probes: Aspects of the Sampling and Miniature Pumping Systems.
J. Am. Soc. Mass Spectrom.
PUBLISHED: 08-26-2014
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Miniature mass spectrometry analytical systems of backpack configuration fitted with sampling probes could potentially be of significant interest for in-field, real-time chemical analysis. In this study, various configurations were explored in which a long narrow tube was used to connect the turbo and backing pumps used to create and maintain vacuum. Also, for the first time we introduced two new types of pumps for miniature mass spectrometers, the Creare 130 g drag pump and Creare 350 g scroll backing pump. These pumps, along with another Creare 550 turbo pump and the commercially available Pfeiffer HiPace 10 turbo and KnF diaphragm backing pumps, were tested with the backpack configurations. The system performance, especially the scan time, was characterized when used with a discontinuous atmospheric pressure interface (DAPI) for ion introduction. The pumping performance in the pressure region above 1 mtorr is critical for DAPI operation. The 550 g turbo pump was shown to have a relatively higher pumping speed above 1 mtorr and gave a scan time of 300 ms, almost half the value obtained with the larger, heavier HiPace 10 often used with miniature mass spectrometers. The 350 g scroll pump was also found to be an improvement over the diaphragm pumps generally used as backing pumps. With a coaxial low temperature plasma ion source, direct analysis of low volatility compounds glass slides was demonstrated, including 1 ng DNP (2,4-Dinitrophenol) and 10 ng TNT (2,4,6-trinitrotoluene) with Creare 550 g turbo pump as well as 10 ng cocaine and 20 ng DNP with Creare 130 g drag pump.
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Genetic variants of CD209 associated with Kawasaki disease susceptibility.
PLoS ONE
PUBLISHED: 08-22-2014
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Kawasaki disease (KD) is a systemic vasculitis with unknown etiology mainly affecting children in Asian countries. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN, CD209) in humans was showed to trigger an anti-inflammatory cascade and associated with KD susceptibility. This study was conducted to investigate the association between genetic polymorphisms of CD209 and the risk KD.
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Immunodeficient mouse models with different disease profiles by in vivo infection with the same clinical isolate of enterovirus 71.
J. Virol.
PUBLISHED: 08-20-2014
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Like poliovirus infection, severe infection with enterovirus 71 (EV71) can cause neuropathology. Unlike poliovirus, EV71 is often associated with hand-foot-and-mouth disease (HFMD). Here we established three mouse models for experimental infection with the same clinical isolate of EV71. The NOD/SCID mouse model is unique for the development of skin rash, an HFMD-like symptom. While the NOD/SCID mice developed limb paralysis and death at near-100% efficiency, the gamma interferon receptor knockout (ifngr KO) and stat-1 knockout mice exhibited paralysis and death rates near 78% and 30%, respectively. Productive infection with EV71 depends on the viral dose, host age, and inoculation route. Levels of infectious EV71, and levels of VP1-specific RNA and protein in muscle, brain, and spinal cord, were compared side by side between the NOD/SCID and stat-1 knockout models before, during, and after disease onset. Spleen fibrosis and muscle degeneration are common in the NOD/SCID and stat-1 knockout models. The main differences between these two models include their disease manifestations and cytokine/chemokine profiles. The pathology of the NOD/SCID model includes (i) inflammation and expression of viral VP1 antigen in muscle, (ii) increased neutrophil levels and decreased eosinophil and lymphocyte levels, and (iii) hair loss and skin rash. The characteristic pathology of the stat-1 knockout model includes (i) a strong tropism of EV71 for the central nervous system, (ii) detection of VP1 protein in the Purkinje layer of cerebellar cortex, pons, brain stem, and spinal cord, (iii) amplification of microglial cells, and (iv) dystrophy of intestinal villi. Our comparative studies on these new models with oral or intraperitoneal (i.p.) infection underscored the contribution of host immunity, including the gamma interferon receptor, to EV71 pathogenesis.
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?-Phellandrene alters expression of genes associated with DNA damage, cell cycle, and apoptosis in murine leukemia WEHI-3 cells.
Anticancer Res.
PUBLISHED: 07-31-2014
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?-phellandrene (?-PA) is a cyclic monoterpene, present in natural plants such as Schinus molle L. ?-PA promotes immune responses in mice in vivo. However, there is no available information on whether ?-PA affects gene expression in leukemia cells. The present study determined effects of ?-PA on expression levels of genes associated with DNA damage, cell cycle and apoptotic cell death in mouse leukemia WEHI-3 cells. WEHI-3 cells were treated with 10 ?M ?-PA for 24 h, cells were harvested and total RNA was extracted, and gene expression was analyzed by cDNA microarray. Results indicated that ?-PA up-regulated 10 genes 4-fold, 13 by over 3-fold and 175 by over 2-fold; 21 genes were down-regulated by over 4-fold, 26 genes by over 3-fold and expression of 204 genes was altered by at leas 2-fold compared with the untreated control cells. DNA damage-associated genes such as DNA damage-inducer transcript 4 and DNA fragmentation factor were up-regulated by 4-fold and over 2-fold, respectively; cell-cycle check point genes such as cyclin G2 and cyclin-dependent kinases inhibitor 2D and IA (p21) were up-regulated by over 3-fold and over 2-fold, respectively; apoptosis-associated genes such as BCL2/adenovirus EIB interacting protein 3, XIAP-associated factor 1, BCL2 modifying factor, caspase-8 and FADD-like apoptosis regulator were over 2-fold up-regulated. Furthermore, DNA damage-associated gene TATA box binding protein was over 4-fold down-regulated, and D19Ertd652c (DNA segment) over 2-fold down-regulated; cell cycle-associated gene cyclin E2 was over 2-fold down-regulated; apoptosis associated gene growth arrest-specific 5 was over 9-fold down-regulated, Gm5426 (ATP synthase) was over 3-fold down-regulated, and death box polypeptide 33 was over 2-fold down-regulated. Based on these observations, ?-PA altered gene expression in WEHI-3 cells in vitro.
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The pathological effects of CCR2+ inflammatory monocytes are amplified by an IFNAR1-triggered chemokine feedback loop in highly pathogenic influenza infection.
J. Biomed. Sci.
PUBLISHED: 07-28-2014
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BackgroundHighly pathogenic influenza viruses cause high levels of morbidity, including excessive infiltration of leukocytes into the lungs, high viral loads and a cytokine storm. However, the details of how these pathological features unfold in severe influenza infections remain unclear. Accumulation of Gr1¿+¿CD11b¿+¿myeloid cells has been observed in highly pathogenic influenza infections but it is not clear how and why they accumulate in the severely inflamed lung. In this study, we selected this cell population as a target to investigate the extreme inflammatory response during severe influenza infection.ResultsWe established H1N1 IAV-infected mouse models using three viruses of varying pathogenicity and noted the accumulation of a defined Gr1¿+¿CD11b¿+¿myeloid population correlating with the pathogenicity. Herein, we reported that CCR2+ inflammatory monocytes are the major cell compartments in this population. Of note, impaired clearance of the high pathogenicity virus prolonged IFN expression, leading to CCR2+ inflammatory monocytes amplifying their own recruitment via an interferon-¿/ß receptor 1 (IFNAR1)-triggered chemokine loop. Blockage of IFNAR1-triggered signaling or inhibition of viral replication by Oseltamivir significantly suppresses the expression of CCR2 ligands and reduced the influx of CCR2+ inflammatory monocytes. Furthermore, trafficking of CCR2+ inflammatory monocytes from the bone marrow to the lung was evidenced by a CCR2-dependent chemotaxis. Importantly, leukocyte infiltration, cytokine storm and expression of iNOS were significantly reduced in CCR2¿/¿ mice lacking infiltrating CCR2+ inflammatory monocytes, enhancing the survival of the infected mice.ConclusionsOur results indicated that uncontrolled viral replication leads to excessive production of inflammatory innate immune responses by accumulating CCR2+ inflammatory monocytes, which contribute to the fatal outcomes of high pathogenicity virus infections.
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A meta-learning approach for B-cell conformational epitope prediction.
BMC Bioinformatics
PUBLISHED: 07-11-2014
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BackgroundOne of the major challenges in the field of vaccine design is identifying B-cell epitopes in continuously evolving viruses. Various tools have been developed to predict linear or conformational epitopes, each relying on different physicochemical properties and adopting distinct search strategies. We propose a meta-learning approach for epitope prediction based on stacked and cascade generalizations. Through meta learning, we expect a meta learner to be able integrate multiple prediction models, and outperform the single best-performing model. The objective of this study is twofold: (1) to analyze the complementary predictive strengths in different prediction tools, and (2) to introduce a generic computational model to exploit the synergy among various prediction tools. Our primary goal is not to develop any particular classifier for B-cell epitope prediction, but to advocate the feasibility of meta learning to epitope prediction. With the flexibility of meta learning, the researcher can construct various meta classification hierarchies that are applicable to epitope prediction in different protein domains.ResultsWe developed the hierarchical meta-learning architectures based on stacked and cascade generalizations. The bottom level of the hierarchy consisted of four conformational and four linear epitope prediction tools that served as the base learners. To perform consistent and unbiased comparisons, we tested the meta-learning method on an independent set of antigen proteins that were not used previously to train the base epitope prediction tools. In addition, we conducted correlation and ablation studies of the base learners in the meta-learning model. Low correlation among the predictions of the base learners suggested that the eight base learners had complementary predictive capabilities. The ablation analysis indicated that the eight base learners differentially interacted and contributed to the final meta model. The results of the independent test demonstrated that the meta-learning approach markedly outperformed the single best-performing epitope predictor.ConclusionsComputational B-cell epitope prediction tools exhibit several differences that affect their performances when predicting epitopic regions in protein antigens. The proposed meta-learning approach for epitope prediction combines multiple prediction tools by integrating their complementary predictive strengths. Our experimental results demonstrate the superior performance of the combined approach in comparison with single epitope predictors.
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Rapid evaluation and quality control of next generation sequencing data with FaQCs.
BMC Bioinformatics
PUBLISHED: 07-03-2014
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BackgroundNext generation sequencing (NGS) technologies that parallelize the sequencing process and produce thousands to millions, or even hundreds of millions of sequences in a single sequencing run, have revolutionized genomic and genetic research. Because of the vagaries of any platform¿s sequencing chemistry, the experimental processing, machine failure, and so on, the quality of sequencing reads is never perfect, and often declines as the read is extended. These errors invariably affect downstream analysis/application and should therefore be identified early on to mitigate any unforeseen effects.ResultsHere we present a novel FastQ Quality Control Software (FaQCs) that can rapidly process large volumes of data, and which improves upon previous solutions to monitor the quality and remove poor quality data from sequencing runs. Both the speed of processing and the required memory footprint of storing all required information have been optimized via algorithmic and parallel processing solutions. The trimmed output compared side-by-side with the original data is part of the automated PDF output. We show how this tool can help data analysis by providing a few examples, including an increased percentage of reads recruited to references, improved single nucleotide polymorphism identification as well as de novo sequence assembly metrics.ConclusionFaQCs combines several features of currently available applications into a single, user-friendly process, and includes additional unique capabilities such as filtering the PhiX control sequences, conversion of FASTQ formats, and multi-threading. The original data and trimmed summaries are reported within a variety of graphics and reports, providing a simple way to do data quality control and assurance.
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Mechanical reinforcement of epoxy with self-assembled synthetic clay in smectic order.
ACS Appl Mater Interfaces
PUBLISHED: 06-27-2014
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Epoxy films containing self-assembled 2D colloidal ?-zirconium phosphate nanoplatelets (ZrP) in smectic order were prepared using a simple, energy-efficient fabrication process suitable to industrial processing. The ZrP nanoplatelets form a chiral smectic mesophase with simultaneous lamellar order and helical arrangements in epoxy. The epoxy nanocomposite films are transparent and flexible and exhibit exceptionally high tensile modulus and strength. The findings have broad implications for development of multifunctional materials for engineering applications.
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Selective inhibition of unfolded protein response induces apoptosis in pancreatic cancer cells.
Oncotarget
PUBLISHED: 06-23-2014
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Endoplasmic reticulum stress from unfolded proteins is associated with the proliferation of pancreatic tumor cells, making the many regulatory molecules of this pathway appealing targets for therapy. The objective of our study was to assess potential therapeutic efficacy of inhibitors of unfolded protein response (UPR) in pancreatic cancers focusing on IRE1? inhibitors. IRE1?-mediated XBP-1 mRNA splicing encodes a transcription factor that enhances transcription of chaperone proteins in order to reverse UPR. Proliferation assays using a panel of 14 pancreatic cancer cell lines showed a dose- and time-dependent growth inhibition by IRE1?-specific inhibitors (STF-083010, 2-Hydroxy-1-naphthaldehyde, 3-Ethoxy-5,6-dibromosalicylaldehyde, toyocamycin). Growth inhibition was also noted using a clonogenic growth assay in soft agar, as well as a xenograft in vivo model of pancreatic cancer. Cell cycle analysis showed that these IRE1? inhibitors caused growth arrest at either the G1 or G2/M phases (SU8686, MiaPaCa2) and induced apoptosis (Panc0327, Panc0403). Western blot analysis showed cleavage of caspase 3 and PARP, and prominent induction of the apoptotic molecule BIM. In addition, synergistic effects were found between either STF-083010, 2-Hydroxy-1-naphthaldehyde, 3-Ethoxy-5,6-dibromosalicylaldehyde, or toyocamycin and either gemcitabine or bortezomib. Our data suggest that use of an IRE1? inhibitor is a novel therapeutic approach for treatment of pancreatic cancers.
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SETDB1 accelerates tumorigenesis by regulating WNT signaling pathway.
J. Pathol.
PUBLISHED: 06-03-2014
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We investigated the oncogenic role of SETDB1 focusing on non-small cell lung cancer (NSCLC) having high expression of this protein. A total of 387 lung cancer cases were examined by immunohistochemistry, 72% of NSCLC samples were positive for SETDB1 staining, compared to 46% samples of normal bronchial epithelium (106 cases) (p?
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The Mechanism of NPC-14686-Induced [Ca²?]i Rises and Non-Ca²?-Triggered Cell Death in MG63 Human Osteosarcoma Cells.
Chin J Physiol
PUBLISHED: 05-16-2014
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NPC-14686 has been shown to have anti-inflammatory effect in previous studies, but the mechanisms are unclear. The effect of NPC-14686 on cytosolic Ca²? concentrations ([Ca²?]i) and viability in MG63 human osteosarcoma cells was explored. The Ca²?-sensitive fluorescent dye fura-2 was applied to measure [Ca²?]i. NPC-14686 at concentrations of 100-500 ?M induced a [Ca²?]i rise in a concentrationdependent manner. The response was reduced by 80% by removing Ca²?. NPC-14686 induced Mn²? influx leading to quenching of fura-2 fluorescence. NPC-14686-evoked Ca²? entry was suppressed by nifedipine, econazole, SK&F96365, and protein kinase C inhibitor. Inhibition of phospholipase C with U73122 abolished NPC-14686-induced [Ca²?]i rise. At 20-50 ?M, NPC-14686 decreased cell viability, which was not reversed by chelating cytosolic Ca²? with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid/acetoxy methyl (BAPTA/AM). Annexin V/propidium iodide staining data suggest that NPC-14686 (30-50 ?M) induced apoptosis in a concentration-dependent manner. NPC-14686 also increased levels of reactive oxygen species. Together, in human osteosarcoma cells, NPC-14686 induced a [Ca²?]i rise by inducing phospholipase C-dependent Ca²? release from the endoplasmic reticulum and Ca²? entry via protein kinase C-sensitive store-operated Ca²? channels. NPC-14686 induced cell death that might involve apoptosis via mitochondrial pathways.
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Nitric oxide production and blood pressure reduction during haemodialysis.
Nephrology (Carlton)
PUBLISHED: 05-13-2014
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A decrease of systolic blood pressure in excess of 20 mmHg during haemodialysis treatment (IDD) is common for haemodialysis patients. Intradialytic hypotension (IDH) is symptomatic IDD by definition. Overproduction of nitric oxide (NO) is a possible cause of IDD. Dialysate nitrate and nitrite amount can be used as an indicator of intradialysis NO production. Our aim was to find the predictor of NO production in IDD patients.
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Melatonin prevents neonatal dexamethasone induced programmed hypertension: Histone deacetylase inhibition.
J. Steroid Biochem. Mol. Biol.
PUBLISHED: 05-11-2014
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Adulthood hypertension can be programmed by corticosteroid exposure in early life. Oxidative stress, epigenetic regulation by histone deacetylases (HDACs), and alterations of renin-angiotensin system (RAS) are involved in the developmental programming of hypertension. We examined whether melatonin prevented neonatal dexamethasone (DEX)-induced programmed hypertension and how melatonin prevented these processes. We also examined whether HDAC inhibition by trichostatin A (TSA, a HDAC inhibitor) had similar effects. Male offspring were assigned to 5 groups (n=6/group): control, DEX, melatonin, DEX+melatonin, and DEX+TSA. Male rat pups were injected i.p. with DEX on day 1 (0.5mg/kg BW), day 2 (0.3mg/kg BW), and day 3 (0.1mg/kg BW) after birth. Melatonin was administered in drinking water at the dose of 0.01% during the lactation period. The DEX+TSA group received DEX and 0.5mg/kg TSA subcutaneous injection once daily for 1 week. All rats were killed at 16 weeks of age. Neonatal DEX exposure induced hypertension in male offspring at 16 weeks of age, which melatonin prevented. Neonatal DEX exposure decreased gene expression related to apoptosis, nephrogenesis, RAS, and sodium transporters. Yet DEX treatment increased protein levels of HDAC-1, -2, and -3 in the kidney. Melatonin therapy preserved the decreases of gene expression and decreased HDACs. Similarly, HDAC inhibition prevented DEX-induced programmed hypertension. In conclusion, melatonin therapy exerts a long-term protection against neonatal DEX-induced programmed hypertension. Its beneficial effects include alterations of RAS components and inhibition of class I HDACs. Given that the similar protective effects of melatonin and TSA, melatonin might inhibit HDACs to epigenetic regulation of hypertension-related genes to prevent programmed hypertension.
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Cardiovascular regenerative therapeutics via synthetic paracrine factor modified mRNA.
Stem Cell Res
PUBLISHED: 04-09-2014
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The heart has a limited capacity for regeneration following injury. Recent strategies to promote heart regeneration have largely focused on autologous and allogeneic cell-based therapy, where the transplanted cells have been suggested to secrete unknown paracrine factors that are envisioned to promote endogenous repair and/or mobilization of endogenous heart progenitors. Here, we discuss the importance of paracrine mechanisms in facilitating replication of endogenous epicardial progenitor cells in the adult heart and signaling their subsequent reactivation and de novo differentiation into functional cell types such as endothelial cells and cardiomyocytes. Moreover, we discuss the use of a novel modified RNA technology in delivering such therapeutic paracrine factors into myocardium following injury. These studies suggest that modified mRNA may be a valuable experimental tool for the precise in vivo identification of paracrine factors and their downstream signaling that may promote heart repair, cardiac muscle replication, and/or heart progenitor mobilization. In addition, these studies lay the foundation for a new clinically tractable technology for a cell-free approach to promote heart regeneration.
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A Chinese herbal medicine, jia-wei-xiao-yao-san, prevents dimethylnitrosamine-induced hepatic fibrosis in rats.
ScientificWorldJournal
PUBLISHED: 04-07-2014
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Jia-wei-xiao-yao-san (JWXYS) is a traditional Chinese herbal medicine that is widely used to treat neuropsychological disorders. Only a few of the hepatoprotective effects of JWXYS have been studied. The aim of this study was to investigate the hepatoprotective effects of JWXYS on dimethylnitrosamine- (DMN-) induced chronic hepatitis and hepatic fibrosis in rats and to clarify the mechanism through which JWXYS exerts these effects. After the rats were treated with DMN for 3 weeks, serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) levels were significantly elevated, whereas the albumin level decreased. Although DMN was continually administered, after the 3 doses of JWXYS were orally administered, the SGOT and SGPT levels significantly decreased and the albumin level was significantly elevated. In addition, JWXYS treatment prevented liver fibrosis induced by DMN. JWXYS exhibited superoxide-dismutase-like activity and dose-dependently inhibited DMN-induced lipid peroxidation and xanthine oxidase activity in the liver of rats. Our findings suggest that JWXYS exerts antifibrotic effects against DMN-induced chronic hepatic injury. The possible mechanism is at least partially attributable to the ability of JWXYS to inhibit reactive-oxygen-species-induced membrane lipid peroxidation.
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Modeling the mitochondrial cardiomyopathy of Barth syndrome with induced pluripotent stem cell and heart-on-chip technologies.
Nat. Med.
PUBLISHED: 03-24-2014
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Study of monogenic mitochondrial cardiomyopathies may yield insights into mitochondrial roles in cardiac development and disease. Here, we combined patient-derived and genetically engineered induced pluripotent stem cells (iPSCs) with tissue engineering to elucidate the pathophysiology underlying the cardiomyopathy of Barth syndrome (BTHS), a mitochondrial disorder caused by mutation of the gene encoding tafazzin (TAZ). Using BTHS iPSC-derived cardiomyocytes (iPSC-CMs), we defined metabolic, structural and functional abnormalities associated with TAZ mutation. BTHS iPSC-CMs assembled sparse and irregular sarcomeres, and engineered BTHS 'heart-on-chip' tissues contracted weakly. Gene replacement and genome editing demonstrated that TAZ mutation is necessary and sufficient for these phenotypes. Sarcomere assembly and myocardial contraction abnormalities occurred in the context of normal whole-cell ATP levels. Excess levels of reactive oxygen species mechanistically linked TAZ mutation to impaired cardiomyocyte function. Our study provides new insights into the pathogenesis of Barth syndrome, suggests new treatment strategies and advances iPSC-based in vitro modeling of cardiomyopathy.
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N-cadherin prevents the premature differentiation of anterior heart field progenitors in the pharyngeal mesodermal microenvironment.
Cell Res.
PUBLISHED: 03-22-2014
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The cardiac progenitor cells (CPCs) in the anterior heart field (AHF) are located in the pharyngeal mesoderm (PM), where they expand, migrate and eventually differentiate into major cell types found in the heart, including cardiomyocytes. The mechanisms by which these progenitors are able to expand within the PM microenvironment without premature differentiation remain largely unknown. Through in silico data mining, genetic loss-of-function studies, and in vivo genetic rescue studies, we identified N-cadherin and interaction with canonical Wnt signals as a critical component of the microenvironment that facilitates the expansion of AHF-CPCs in the PM. CPCs in N-cadherin mutant embryos were observed to be less proliferative and undergo premature differentiation in the PM. Notably, the phenotype of N-cadherin deficiency could be partially rescued by activating Wnt signaling, suggesting a delicate functional interaction between the adhesion role of N-cadherin and Wnt signaling in the early PM microenvironment. This study suggests a new mechanism for the early renewal of AHF progenitors where N-cadherin provides additional adhesion for progenitor cells in the PM, thereby allowing Wnt paracrine signals to expand the cells without premature differentiation.Cell Research advance online publication 4 November 2014; doi:10.1038/cr.2014.142.
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Aberrant expression of annexin A10 is closely related to gastric phenotype in serrated pathway to colorectal carcinoma.
Mod. Pathol.
PUBLISHED: 03-14-2014
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Annexin A10 (ANXA10) is a member of the ANX family that is normally expressed in gastric mucosa. ANXA10 was recently observed to be upregulated in sessile serrated adenoma, a precursor to microsatellite-unstable colorectal cancer. We investigated the use of ANXA10 in diagnosing colorectal carcinoma. In an immunohistochemical analysis, the intensity and quantity of ANXA10, MUC5AC, MUC6 and CDX2 in 123 colorectal carcinomas were graded. We determined the molecular status of BRAF and KRAS mutations, as well as the microsatellite instability status and the CpG island methylator phenotype in all colorectal carcinomas, and subcategorized into four molecular subgroups according to the molecular derangements. Nuclear ANXA10 staining was present in 36 colorectal carcinomas, exhibiting a strong significant association with the BRAF mutation status (P<0.0001) and positive CpG island methylator phenotype (P<0.0001), and a borderline significant association with high levels of microsatellite instability (P=0.072). The ANXA10-positive colorectal carcinomas were frequently positive for MUC5AC and MUC6, and were associated with absent or reduced CDX2 expression (all P<0.0001). According to a classification and regression tree analysis, ANXA10 is a superior marker for the molecular subtyping of colorectal carcinomas and represents a specific marker for colorectal cancers of the serrated pathway. Our results indicated that ANXA10 expression is implicated in gastric programming in serrated-pathway-associated colorectal carcinoma. ANXA10-positive colorectal carcinoma is highly associated with the molecular features of the serrated neoplasia pathway.Modern Pathology advance online publication, 1 August 2014; doi:10.1038/modpathol.2014.96.
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Common carotid artery intima-media thickness is useful for diagnosis of the acute stage of Kawasaki disease.
BMC Pediatr
PUBLISHED: 03-13-2014
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This study aimed to investigate intima-media thickness (IMT) of the common carotid arteries in children with acute Kawasaki disease (KD).
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Manipulation of a VEGF-Notch signaling circuit drives formation of functional vascular endothelial progenitors from human pluripotent stem cells.
Cell Res.
PUBLISHED: 03-10-2014
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Human pluripotent stem cell (hPSC)-derived endothelial lineage cells constitutes a promising source for therapeutic revascularization, but progress in this arena has been hampered by a lack of clinically-scalable differentiation protocols and inefficient formation of a functional vessel network integrating with the host circulation upon transplantation. Using a human embryonic stem cell reporter cell line, where green fluorescent protein expression is driven by an endothelial cell-specific VE-cadherin (VEC) promoter, we screened for > 60 bioactive small molecules that would promote endothelial differentiation, and found that administration of BMP4 and a GSK-3? inhibitor in an early phase and treatment with VEGF-A and inhibition of the Notch signaling pathway in a later phase led to efficient differentiation of hPSCs to the endothelial lineage within six days. This sequential approach generated > 50% conversion of hPSCs to endothelial cells (ECs), specifically VEC(+)CD31(+)CD34(+)CD14(-)KDR(high) endothelial progenitors (EPs) that exhibited higher angiogenic and clonogenic proliferation potential among endothelial lineage cells. Pharmaceutical inhibition or genetical knockdown of Notch signaling, in combination with VEGF-A treatment, resulted in efficient formation of EPs via KDR(+) mesodermal precursors and blockade of the conversion of EPs to mature ECs. The generated EPs successfully formed functional capillary vessels in vivo with anastomosis to the host vessels when transplanted into immunocompromised mice. Manipulation of this VEGF-A-Notch signaling circuit in our protocol leads to rapid large-scale production of the hPSC-derived EPs by 12- to 20-fold vs current methods, which may serve as an attractive cell population for regenerative vascularization with superior vessel forming capability compared to mature ECs.
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Autonomous in situ analysis and real-time chemical detection using a backpack miniature mass spectrometer: concept, instrumentation development, and performance.
Anal. Chem.
PUBLISHED: 02-24-2014
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A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1-2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.
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Cantharidin induces apoptosis of H460 human lung cancer cells through mitochondria-dependent pathways.
Int. J. Oncol.
PUBLISHED: 02-14-2014
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Lung cancer is one of the leading causes of death in cancer-related diseases. Cantharidin (CTD) is one of the components of natural mylabris (Mylabris phalerata Pallas). Numerous studies have shown that CTD induced cytotoxic effects on cancer cells. However, there is no report to demonstrate that CTD induced apoptosis in human lung cancer cells. Herein, we investigated the effect of CTD on the cell death via the induction of apoptosis in H460 human lung cancer cells. Flow cytometry assay was used for examining the percentage of cell viability, sub-G1 phase of the cell cycle, reactive oxygen species (ROS) and Ca²? productions and the levels of mitochondrial membrane potential (??m). Annexin V/PI staining and DNA gel electrophoresis were also used for examining cell apoptosis. Western blot analysis was used to examine the changes of apoptosis associated protein expression and confocal microscopy for examining the translocation apoptosis associated protein. Results indicated that CTD significantly induced cell morphological changes and decreased the percentage of viable H460 cells. CTD induced apoptosis based on the occurrence of sub-G1 phase and DNA fragmentation. We found that CTD increased gene expression (mRNA) of caspase-3 and -8. Moreover, CTD increased ROS and Ca2+ production and decreased the levels of ??m. Western blot analysis results showed that CTD increased the expression of cleavage caspase-3 and -8, cytochrome c, Bax and AIF but inhibited the levels of Bcl-xL. CTD promoted ER stress associated protein expression such as GRP78, IRE1?, IRE1?, ATF6? and caspase-4 and it also promoted the expression of calpain 2 and XBP-1, but inhibited calpain 1 that is associated with apoptosis pathways. Based on those observations, we suggest that CTD may be used as a novel anticancer agent for the treatment of lung cancer in the future.
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Genetic polymorphisms of ORAI1 and chronic kidney disease in Taiwanese population.
Biomed Res Int
PUBLISHED: 02-06-2014
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Taiwan has very high incidence and prevalence of chronic kidney disease (CKD), which easily progresses to end-stage renal disease (ESRD). The association between inflammation and CKD has been explored in several studies. ORAI1 functions as a pore-forming subunit of the store-operated calcium channels which are involved in the regulation of immune system. Hence, we conducted a case-control study to determine whether the genetic polymorphisms of ORAI1 gene is a susceptibility factor to CKD and its clinical features in a Taiwanese population. Five hundred seventy-nine CKD patients from a hospital-based CKD care program were included in the study. Five tagging single nucleotide polymorphisms (tSNPs) of ORAI1 were selected from the genotyping data of the Han Chinese population from the HapMap project. Among these polymorphisms, rs12313273 was found to be significantly associated with elevated serum calcium levels, which has been linked to increased risk of death in CKD patients. To have a better management of serum calcium, we suggest that ORAI1 polymorphisms might be used as a potential biomarker for initiating non-calcium-based phosphate binder in CKD patients in the future.
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Effects of diallyl trisulfide on induction of apoptotic death in murine leukemia WEHI-3 cells in vitro and alterations of the immune responses in normal and leukemic mice in vivo.
Environ. Toxicol.
PUBLISHED: 01-27-2014
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Diallyl trisulfide (DATS), a chemopreventive dietary constituent and extracted from garlic, has been shown to against cultured many types of human cancer cell liens but the fate of apoptosis in murine leukemia cells in vitro and immune responses in leukemic mice remain elusive. Herein, we clarified the actions of DATS on growth inhibition of murine leukemia WEHI-3 cells in vitro and used WEHI-3 cells to generate leukemic mice in vivo, following to investigate the effects of DATS in animal model. In in vitro study, DATS induced apoptosis of WEHI-3 cells through the G0/G1 phase arrest and induction of caspase-3 activation. In in vivo study DATS decreased the weight of spleen of leukemia mice but did not affect the spleen weight of normal mice. DATS promoted the immune responses such as promotions of the macrophage phagocytosis and NK cell activities in WEHI-3 leukemic and normal mice. However, DATS only promotes NK cell activities in normal mice. DATS increases the surface markers of CD11b and Mac-3 in leukemia mice but only promoted CD3 in normal mice. In conclusion, the present study indicates that DATS induces cell death through induction of apoptosis in mice leukemia WHEI-3 cells. DATS also promotes immune responses in leukemia and normal mice in vivo. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.
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Gallic Acid Exhibits Risks of Inducing Muscular Hemorrhagic Liposis and Cerebral Hemorrhage-Its Action Mechanism and Preventive Strategy.
Phytother Res
PUBLISHED: 01-18-2014
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Gallic acid (3,4,5-trihydroxybenzoic acid) (GA) occurs in many plants. The adverse effects of GA are seldom cited. GA (6-14??M) provoked the hemorrhagic liposis of the cervical muscles and intracranial hemorrhage. The cause of these pathological events and the method for prevention are still lacking. Using the chicken embryo model and some selected nutraceutics such as folate, glutathione (GSH), N-acetylcysteine, and vitamin E (Vit E), we carried out this study. Results revealed that the action mechanism of GA involved (i) inducing hypoxia with upregulated gene hif-1? and downregulated ratio vegf-r2/vegf-a, leading to dys-vascularization and myopathy; (ii) impairing cytochrome c oxidase; (iii) stimulating creatine kinase and lactate dehydrogenase release; (iv) eliciting carnitine accumulation and liposis via downregulating gene CPT1; (v) suppressing superoxide dismutase and stimulating NO, H2 O2 , and malondialdehyde; and (vi) depleting erythrocytic and tissue GSH, resulting in hemorrhage. When both Vit E and GSH were applied to the day?1 chicks, a better alleviation effect was revealed. Conclusively, GA potentially exhibits adverse effect by eliciting hemorrhagic liposis of cervical muscles and cerebral hemorrhage. Supplementation with GSH, Vit E, and N-acetylcysteine is able to ameliorate these adverse effects, warranting the importance of restricting the clinical phytotherapeutic doses of GA and related compounds. Copyright © 2014 John Wiley & Sons, Ltd.
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Occurrence of aryl hydrocarbon receptor agonists and genotoxic compounds in the river systems in Southern Taiwan.
Chemosphere
PUBLISHED: 01-08-2014
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Water and sediment samples from river systems located in Southern Taiwan were investigated for the presence of aryl hydrocarbon receptor (AhR) agonists and genotoxicants by a combination of recombinant cell assays and gas chromatography-mass spectrometry analysis. AhR agonist activity and genotoxic response were frequently detected in samples collected during different seasons. In particular, dry-season water and sediment samples from Erren River showed strong AhR agonist activity (201-1423 ng L(-1) and 1374-5631 ng g(-1) ?-naphthoflavone equivalents) and high genotoxic potential. Although no significant correlation was found between AhR agonist activity and genotoxicity, potential genotoxicants in sample extracts were suggested to be causative agents for yeast growth inhibition in the AhR-responsive reporter gene assay. After high performance liquid chromatography fractionation, AhR agonist candidates were detected in several fractions of Erren River water and sediment extracts, while possible genotoxicants were only found in water extracts. In addition, polycyclic aromatic hydrocarbons, the typical contaminants showing high AhR binding affinity, were only minor contributors to the AhR agonist activity detected in Erren River sediment extracts. Our findings displayed the usefulness of bioassays in evaluating the extent of environmental contamination, which may be helpful in reducing the chances of false-negative results obtained from chemical analysis of conventional contaminants. Further research will be undertaken to identify major candidates for xenobiotic AhR agonists and genotoxicants to better protect the aquatic environments in Taiwan.
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Diallyl trisulfide inhibits migration, invasion and angiogenesis of human colon cancer HT-29 cells and umbilical vein endothelial cells, and suppresses murine xenograft tumour growth.
J. Cell. Mol. Med.
PUBLISHED: 01-07-2014
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Angiogenesis inhibitors are beneficial for the prevention and treatment of angiogenesis-dependent diseases including cancer. We examined the cytotoxic, anti-metastatic, anti-cancer and anti-angiogenic effects of diallyl trisulfide (DATS). In HT29 cells, DATS inhibited migration and invasion through the inhibition of focal adhesion kinase (FAK), extracellular signal-regulated kinase, c-Jun N-terminal kinase and p38 which was associated with inhibition of matrix metalloproteinases-2, -7 and -9 and VEGF. In human umbilical vein endothelial cells (HUVEC), DATS inhibited the migration and angiogenesis through FAK, Src and Ras. DATS also inhibited the secretion of VEGF. The capillary-like tube structure formation and migration by HUVEC was inhibited by DATS. The chicken egg chorioallantoic membrane (CAM) assay indicated that DATS treatment inhibited ex-vivo angiogenesis. We investigated the anti-tumour effects of DATS against human colon cancer xenografts in BALB/c(nu/nu) mice and its anti-angiogenic activity in vivo. In this in-vivo study, DATS also inhibited the tumour growth, tumour weight and angiogenesis (decreased the levels of haemoglobin) in HT29 cells. In conclusion, the present results suggest that the inhibition of angiogenesis may be an important mechanism in colon cancer chemotherapy by DATS.
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Occurrence of xenobiotic ligands for retinoid X receptors and thyroid hormone receptors in the aquatic environment of Taiwan.
Mar. Pollut. Bull.
PUBLISHED: 01-07-2014
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Various synthetic compounds are frequently discharged into the environment via human activities. Among them, certain contaminants may disrupt normal physiological functions of wildlife and humans via interactions with nuclear receptors. To protect human health and the environment, it is important to detect environmental ligands for human nuclear receptors. In this study, yeast-based reporter gene assays were used to investigate the occurrence of xenobiotic ligands for retinoid X receptors (RXR) and thyroid hormone receptors (TR) in the aquatic environment of Taiwan. Experimental results revealed that RXR agonist/antagonist activity was detected in river water and sediment samples. In particular, high RXR agonist/antagonist activity was found in the samples collected near river mouths. Additionally, few samples also elicited significant TR antagonist activity. Our findings show that the aquatic environment of Taiwan was contaminated with RXR and TR ligands. Further study is necessary to identify these xenobiotic RXR and TR agonists and antagonists.
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Adjunctive traditional Chinese medicine therapy improves survival in patients with advanced breast cancer: a population-based study.
Cancer
PUBLISHED: 01-02-2014
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Traditional Chinese medicine (TCM) is one of the most common complementary and alternative medicines used in the treatment of patients with breast cancer. However, the clinical effect of TCM on survival, which is a major concern in these individuals, lacks evidence from large-scale clinical studies.
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Differential Regulation of Human Aortic Smooth Muscle Cell Proliferation by Monocyte-Derived Macrophages from Diabetic Patients.
PLoS ONE
PUBLISHED: 01-01-2014
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Macrophage accumulation in the arterial wall and smooth muscle cell (SMC) proliferation are features of type 2 diabetes mellitus (DM) and its vascular complications. However, the effects of diabetic monocyte-derived macrophages on vascular SMC proliferation are not clearly understood. In the present study, we investigated the pro-proliferative effect of macrophages isolated from DM patients on vascular SMCs. Macrophage-conditioned media (MCM) were prepared from macrophages isolated from DM patients. DM-MCM treatment induced HASMC proliferation, decreased p21Cip1 and p27Kip1 expressions, and increased microRNA (miR)-17-5p and miR-221 expressions. Inhibition of either miR-17-5p or miR-221 inhibited DM-MCM-induced cell proliferation. Inhibition of miR-17-5p abolished DM-MCM-induced p21Cip1 down-regulation; and inhibition of miR-221 attenuated the DM-MCM-induced p27Kip1 down-regulation. Furthermore, blocking assays demonstrated that PDGF-CC in DM-MCM is the major mediators of cell proliferation in SMCs. In conclusion, our present data support the hypothesis that SMC proliferation stimulated by macrophages may play critical roles in vascular complications in DM patients and suggest a new mechanism by which arterial disease is accelerated in diabetes.
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Enhanced Cytotoxicity of Natural Killer Cells following the Acquisition of Chimeric Antigen Receptors through Trogocytosis.
PLoS ONE
PUBLISHED: 01-01-2014
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Natural killer (NK) cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs), which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL) cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.
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The muscle ankyrin repeat proteins CARP, Ankrd2, and DARP are not essential for normal cardiac development and function at basal conditions and in response to pressure overload.
PLoS ONE
PUBLISHED: 01-01-2014
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Ankrd1/CARP, Ankrd2/Arpp, and Ankrd23/DARP belong to a family of stress inducible ankyrin repeat proteins expressed in striated muscle (MARPs). The MARPs are homologous in structure and localized in the nucleus where they negatively regulate gene expression as well as in the sarcomeric I-band, where they are thought to be involved in mechanosensing. Together with their strong induction during cardiac disease and the identification of causative Ankrd1 gene mutations in cardiomyopathy patients, this suggests their important roles in cardiac development, function, and disease. To determine the functional role of MARPs in vivo, we studied knockout (KO) mice of each of the three family members. Single KO mice were viable and had no apparent cardiac phenotype. We therefore hypothesized that the three highly homologous MARP proteins may have redundant functions in the heart and studied double and triple MARP KO mice. Unexpectedly, MARP triple KO mice were viable and had normal cardiac function both at basal levels and in response to mechanical pressure overload induced by transverse aortic constriction as assessed by echocardiography and hemodynamic studies. Thus, CARP, Ankrd2, and DARP are not essential for normal cardiac development and function at basal conditions and in response to mechanical pressure overload.
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Single-nucleotide polymorphism rs7251246 in ITPKC is associated with susceptibility and coronary artery lesions in Kawasaki disease.
PLoS ONE
PUBLISHED: 01-01-2014
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Kawasaki disease (KD) is a multi-systemic vasculitis that preferentially affects children. A single nucleotide polymorphism (SNP) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) has been identified to be an important polymorphism in the risk of KD. This study was conducted to comprehensively investigate the associations between all tagging SNPs of ITPKC in the risk of KD in a Taiwanese population. A total of 950 subjects (381 KD patients and 569 controls) were recruited. Seven tagging SNPs (rs11673492, rs7257602, rs7251246, rs890934, rs10420685, rs2607420, rs2290692) were selected for TaqMan allelic discrimination assay. Clinical data of coronary artery lesions (CAL) and aneurysms were collected for analysis. A significant association was found between rs7251246 in ITPKC and CAL formation. Haplotype analysis for ITPKC polymorphisms also confirmed this association in the patients with CAL and aneurysm formation. This is the first study to identify that SNP rs7251246 in ITPKC is associated with the severity of KD.
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Recruiting human microbiome shotgun data to site-specific reference genomes.
PLoS ONE
PUBLISHED: 01-01-2014
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The human body consists of innumerable multifaceted environments that predispose colonization by a number of distinct microbial communities, which play fundamental roles in human health and disease. In addition to community surveys and shotgun metagenomes that seek to explore the composition and diversity of these microbiomes, there are significant efforts to sequence reference microbial genomes from many body sites of healthy adults. To illustrate the utility of reference genomes when studying more complex metagenomes, we present a reference-based analysis of sequence reads generated from 55 shotgun metagenomes, selected from 5 major body sites, including 16 sub-sites. Interestingly, between 13% and 92% (62.3% average) of these shotgun reads were aligned to a then-complete list of 2780 reference genomes, including 1583 references for the human microbiome. However, no reference genome was universally found in all body sites. For any given metagenome, the body site-specific reference genomes, derived from the same body site as the sample, accounted for an average of 58.8% of the mapped reads. While different body sites did differ in abundant genera, proximal or symmetrical body sites were found to be most similar to one another. The extent of variation observed, both between individuals sampled within the same microenvironment, or at the same site within the same individual over time, calls into question comparative studies across individuals even if sampled at the same body site. This study illustrates the high utility of reference genomes and the need for further site-specific reference microbial genome sequencing, even within the already well-sampled human microbiome.
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Laminin-5?-2 (LAMC2) Is Highly Expressed in Anaplastic Thyroid Carcinoma and Is Associated With Tumor Progression, Migration, and Invasion by Modulating Signaling of EGFR.
J. Clin. Endocrinol. Metab.
PUBLISHED: 12-20-2013
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Context: Anaplastic thyroid carcinoma (ATC) is an aggressive malignancy having no effective treatment. Laminin subunit-?-2 (LAMC2) is an epithelial basement membrane protein involved in cell migration and tumor invasion and might represent an ideal target for the development of novel therapeutic approaches for ATC. Objective: The objective of the investigation was to study the role of LAMC2 in ATC tumorigenesis. Design: LAMC2 expression was evaluated by RT-PCR, Western blotting, and immunohistochemistry in tumor specimens, adjacent noncancerous tissues, and cell lines. The short hairpin RNA (shRNA) approach was used to investigate the effect of LAMC2 knockdown on the tumorigenesis of ATC. Results: LAMC2 was highly expressed in ATC samples and cell lines compared with normal thyroid tissues. Silencing LAMC2 by shRNA in ATC cells moderately inhibited cell growth in liquid culture and dramatically decreased growth in soft agar and in xenografts growing in immunodeficient mice. Silencing LAMC2 caused cell cycle arrest and significantly suppressed the migration, invasion, and wound healing of ATC cells. Rescue experiments by overexpressing LAMC2 in LAMC2 knockdown cells reversed the inhibitory effects as shown by increased cell proliferation and colony formation. Microarray data demonstrated that LAMC2 shRNA significantly altered the expression of genes associated with migration, invasion, proliferation, and survival. Immunoprecipitation studies showed that LAMC2 bound to epidermal growth factor receptor (EGFR) in the ATC cells. Silencing LAMC2 partially blocked epidermal growth factor-mediated activation of EGFR and its downstream pathway. Interestingly, cetuximab (an EGFR blocking antibody) or EGFR small interfering RNA additively enhanced the antiproliferative activity of the LAMC2 knockdown ATC cells compared with the control cells. Conclusions: To our knowledge, this is the first report investigating the effect of LAMC2 on cell growth, cell cycle, migration, invasion, and EGFR signaling in ATC cells, suggesting that LAMC2 may be a potential therapeutic target for the treatment of ATC.
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Folic acid supplementation in end-stage renal disease patients reduces total mortality rate.
J. Nephrol.
PUBLISHED: 12-05-2013
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Background: Patients with end-stage renal disease (ESRD) are at high risk of cardiovascular disease and elevated serum homocysteine levels. Although folic acid supplementation has been documented to reduce serum homocysteine levels in ESRD patients, most trials of folic acid therapy for reducing cardiovascular diseases in ESRD patients have failed, mainly because of limited patient numbers.?Methods: We used the Taiwan National Health Insurance Research Database (NHIRD) to conduct a matched-pair retrospective cohort study to clarify whether folic acid supplementation benefits ESRD patient survival. Patients were divided into a folic acid supplementation group and a control group. All-cause and cardiovascular-related mortality rates between groups were compared.?Results: In total, 55,636 stable incident hemodialysis patients were identified from the database. Using a propensity score-matched method and intention-to-treat analysis, the survival rate of 17,000 patients with folic acid supplementation was compared with a 1:1 matched control group. The baseline demographic data and comorbid disease incidence between the 2 groups were comparable. During the study period, the mortality rate in the matched pair cohort was 35.5% (n = 6,030) over a mean follow-up period of ?3.0 years, corresponding to a mortality rate of 12.8/100 patient-years. The all-cause mortality rates were 12.3 and 13.4/100 patient-years in the folic acid group and control group, respectively (p = 0.005). ?Conclusions: In adult hemodialysis patients, folic acid supplementation improves cardiovascular and all-cause mortality rates.
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Development of a mass spectrometry sampling probe for chemical analysis in surgical and endoscopic procedures.
Anal. Chem.
PUBLISHED: 11-22-2013
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A sampling probe based on ambient desorption ionization was designed for in vivo chemical analysis by mass spectrometry in surgical and endoscopic procedures. Sampling ionization of analytes directly from tissue was achieved by sealing the sampling tip against the tissue surface without allowing leakage of the auxiliary gas used for desorption ionization. The desorbed charged species were transferred over a long distance (up to 4 m) through a flexible tube of internal diameter as small as 1/16 in. to the inlet of the mass spectrometer used for analysis. The conditions used for desorption electrospray ionization (DESI) were optimized to achieve biocompatibility for clinical applications while obtaining adequate efficiency for the analysis. This optimization involved the removal of high voltage and use of pure water as a spray solvent instead of the organic solvents or aqueous mixtures normally used. Improved sensitivity was achieved under these conditions by increasing the gas flow rate in the transfer tube. The destructive effect on tissue surfaces associated with typical desorption ionization was avoided by altering the local gas dynamics in the sample area without compromising the overall analysis efficiency.
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Functional Differences in Engineered Myocardium from Embryonic Stem Cell-Derived versus Neonatal Cardiomyocytes.
Stem Cell Reports
PUBLISHED: 11-19-2013
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Stem cell-derived cardiomyocytes represent unique tools for cell- and tissue-based regenerative therapies, drug discovery and safety, and studies of fundamental heart-failure mechanisms. However, the degree to which stem cell-derived cardiomyocytes compare to mature cardiomyocytes is often debated. We reasoned that physiological metrics of engineered cardiac tissues offer a means of comparison. We built laminar myocardium engineered from cardiomyocytes that were differentiated from mouse embryonic stem cell-derived cardiac progenitors or harvested directly from neonatal mouse ventricles, and compared their anatomy and physiology in vitro. Tissues assembled from progenitor-derived myocytes and neonate myocytes demonstrated similar cytoskeletal architectures but different gap junction organization and electromechanical properties. Progenitor-derived myocardium had significantly less contractile stress and slower longitudinal conduction velocity than neonate-derived myocardium, indicating that the developmental state of the cardiomyocytes affects the electromechanical function of the resultant engineered tissue. These data suggest a need to establish performance metrics for future stem cell applications.
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Accuracy of faecal occult blood test and Helicobacter pylori stool antigen test for detection of upper gastrointestinal lesions.
BMJ Open
PUBLISHED: 11-02-2013
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Highly sensitive guaiac-based faecal occult blood (Hemoccult SENSA) and Helicobacter pylori stool antigen testing might help detect upper gastrointestinal lesions when appended to a colorectal cancer screening programme with faecal immunochemical testing. We evaluated the diagnostic accuracies of two stool tests in detecting upper gastrointestinal lesions.
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A type I IFN-Flt3 ligand axis augments plasmacytoid dendritic cell development from common lymphoid progenitors.
J. Exp. Med.
PUBLISHED: 10-21-2013
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During infections and inflammation, plasmacytoid dendritic cells (pDCs) are the most potent type I interferon (IFN-I)-producing cells. However, the developmental origin of pDCs and the signals dictating pDC generation remain incompletely understood. Here, we report a synergistic role for IFN-I and Flt3 ligand (FL) in pDC development from common lymphoid progenitors (CLPs). Both conventional DCs (cDCs) and pDCs were generated from CLPs in response to FL, whereas pDC generation required higher concentrations of FL and concurrent IFN-I signaling. An absence of IFN-I receptor, impairment of IFN-I signaling, or neutralization of IFN-I significantly impeded pDC development from CLPs. Furthermore, FL induced IFN-I expression in CLPs, which in turn induced Flt3 up-regulation that facilitated survival and proliferation of CLPs, as well as their differentiation into pDCs. Collectively, these results define a critical role for the FL/IFN-I/Flt3 axis in pDC differentiation from CLPs.
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Embryonic heart progenitors and cardiogenesis.
Cold Spring Harb Perspect Med
PUBLISHED: 10-03-2013
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The mammalian heart is a highly specialized organ, comprised of many different cell types arising from distinct embryonic progenitor populations during cardiogenesis. Three precursor populations have been identified to contribute to different myocytic and nonmyocytic cell lineages of the heart: cardiogenic mesoderm cells (CMC), the proepicardium (PE), and cardiac neural crest cells (CNCCs). This review will focus on molecular cues necessary for proper induction, expansion, and lineage-specific differentiation of these progenitor populations during cardiac development in vivo. Moreover, we will briefly discuss how the knowledge gained on embryonic heart progenitor biology can be used to develop novel therapeutic strategies for the management of congenital heart disease as well as for improvement of cardiac function in ischemic heart disease.
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Direct cardiomyocyte reprogramming: a new direction for cardiovascular regenerative medicine.
Cold Spring Harb Perspect Med
PUBLISHED: 09-05-2013
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The past few years have seen unexpected new developments in direct cardiomyocyte reprogramming. Direct cardiomyocyte reprogramming potentially offers an entirely novel approach to cardiovascular regenerative medicine by converting cardiac fibroblasts into functional cardiomyocytes in situ. There is much to be learned, however, about the mechanisms of direct reprogramming in order that the process can be made more efficient. Early efforts have suggested that this new technology can be technically challenging. Moreover, new methods of inducing heart reprogramming will need to be developed before this approach can be translated to the bedside. Despite this, direct cardiomyocyte reprogramming may lead to new therapeutic options for sufferers of heart disease.
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The years of the monkey.
Cell Res.
PUBLISHED: 08-20-2013
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The fact that mammals are diploid sets a barrier to rapidly understand the function of non-coding and coding genes in the genome. Recently, Yang et al. reported successful derivation of monkey haploid embryonic stem cells from parthenotes, which provide an effective platform for studying mammalian gene function and enable reverse genetic screening of genes for recessive phenotypes in monkeys.
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Sensitivity enhancement of electro-optic polymer probing system using photo-isomerization and Fabry-Pe?rot effects.
Rev Sci Instrum
PUBLISHED: 08-02-2013
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A sensitivity enhancement method for an external electro-optic (EO) probing system using a poled polymer as an EO sensor is proposed. A pumping laser, which induces the photo-isomerization effect in a prepoled EO polymer, and a tunable probing laser, which induces Fabry-Pe?rot effect, are combined to enhance the polymer EO sensor sensitivity. Results of an experiment with an EO sensor made of Disperse Red 1 poly(methy1 methacrylate) that demonstrates this combined effect are reported.
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Effects of quality assurance regulatory enforcement on performance of mammography systems: evidence from large-scale surveys in Taiwan.
AJR Am J Roentgenol
PUBLISHED: 07-26-2013
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The Standards for Medical Exposure Quality Assurance in mammography systems were enacted on July 1, 2008, in Taiwan. This study aimed to evaluate the trends in performance of mammography units before and after the regulation started on the basis of annual on-site surveys from 2008 to 2010.
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A HCN4+ cardiomyogenic progenitor derived from the first heart field and human pluripotent stem cells.
Nat. Cell Biol.
PUBLISHED: 07-15-2013
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Most of the mammalian heart is formed from mesodermal progenitors in the first and second heart fields (FHF and SHF), whereby the FHF gives rise to the left ventricle and parts of the atria and the SHF to the right ventricle, outflow tract and parts of the atria. Whereas SHF progenitors have been characterized in detail, using specific molecular markers, comprehensive studies on the FHF have been hampered by the lack of exclusive markers. Here, we present Hcn4 (hyperpolarization-activated cyclic nucleotide-gated channel 4) as an FHF marker. Lineage-traced Hcn4+/FHF cells delineate FHF-derived structures in the heart and primarily contribute to cardiomyogenic cell lineages, thereby identifying an early cardiomyogenic progenitor pool. As a surface marker, HCN4 also allowed the isolation of cardiomyogenic Hcn4+/FHF progenitors from human embryonic stem cells. We conclude that a primary purpose of the FHF is to generate cardiac muscle and support the contractile activity of the primitive heart tube, whereas SHF-derived progenitors contribute to heart cell lineage diversification.
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Draft Genome Sequence of Methylomicrobium buryatense Strain 5G, a Haloalkaline-Tolerant Methanotrophic Bacterium.
Genome Announc
PUBLISHED: 07-02-2013
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Robust growth of the gammaproteobacterium Methylomicrobium buryatense strain 5G on methane makes it an attractive system for CH4-based biocatalysis. Here we present a draft genome sequence of the strain that will provide a valuable framework for metabolic engineering of the core pathways for the production of valuable chemicals from methane.
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RNA silencing targeting PIN (protein inhibitor of neuronal nitric oxide synthase) attenuates the development of hypertension in young spontaneously hypertensive rats.
J Am Soc Hypertens
PUBLISHED: 07-01-2013
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Nitric oxide (NO) deficiency contributes to hypertension. We previously showed that neuronal nitric oxide synthase (nNOS) was involved in hypertension and kidney damage in spontaneously hypertensive rats (SHRs). The protein inhibitor of nNOS (PIN) has been reported to inhibit activity of nNOS.Thus, we tested whether increased PIN in the kidney results in hypertension and whether small interfering RNA (siRNA) targeting PIN attenuates hypertension in SHRs. Four-week-old male SHRs were assigned into three groups (n = 6-7/group): SHR; SHR + PIN, SHR that received siRNA targeting PIN; and SHR + NC, SHR treated with random negative control siRNA. Rats were sacrificed at 12 weeks of age. PIN protein expression was inhibited considerably when PIN siRNA was transfected into NRK52E cells (90% siRNA at 1 nM). The increases of BP were attenuated by siRNA targeting PIN in12-week-old SHRs. Immunostaining of nNOS-? and total nNOS was greater in SHR + PIN group than SHR. Moreover, renal superoxide production and 8-hydroxydeoxyguanosine (8-OHdG) staining were more decreased in the SHR + PIN group than SHRs. We conclude that PIN siRNA reduced PIN expression in vitro and in vivo. PIN siRNA therapy attenuates hypertension in SHRs at 12 weeks of age. Our results suggest that PIN is involved in the development of hypertension.
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Two different approaches to restore renal nitric oxide and prevent hypertension in young spontaneously hypertensive rats: l-citrulline and nitrate.
Transl Res
PUBLISHED: 06-27-2013
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Nitric oxide (NO) deficiency mediates oxidative stress in the kidney and is involved in the development of hypertension. NO synthesis occurs via 2 pathways: nitric oxide synthase (NOS) dependent and NOS-independent. We tested whether the development of hypertension is prevented by restoration of NO by dietary l-citrulline or nitrate supplementation in young spontaneously hypertensive rats (SHRs). Male SHRs and normotensive Wistar Kyoto control rats (WKYs)s age 4 weeks were assigned to 4 groups: untreated SHRs and WKYs, and SHRs and WKYs that received 0.25% l-citrulline for 8 weeks. In our second series of studies, we replaced l-citrulline with 1 mmol/kg/d sodium nitrate. All rats were sacrificed at age 12 weeks. We found an increase in the blood pressure of SHRs was prevented by dietary supplementation of l-citrulline or nitrate. Both treatments restored NO bioavailability and reduced oxidative stress in SHR kidneys. l-Citrulline therapy reduced levels of l-arginine and asymmetric dimethylarginine (ADMA)-an endogenous inhibitor of NOS-and increased the l-arginine-to-ADMA ratio in SHR kidneys. Nitrate treatment reduced plasma levels of l-arginine and ADMA concurrently in SHRs. Our findings suggest that both NOS-dependent and -independent approaches in the prehypertensive stage toward augmentation of NO can prevent the development of hypertension in young SHRs.
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Modified mRNA directs the fate of heart progenitor cells and induces vascular regeneration after myocardial infarction.
Nat. Biotechnol.
PUBLISHED: 05-10-2013
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In a cell-free approach to regenerative therapeutics, transient application of paracrine factors in vivo could be used to alter the behavior and fate of progenitor cells to achieve sustained clinical benefits. Here we show that intramyocardial injection of synthetic modified RNA (modRNA) encoding human vascular endothelial growth factor-A (VEGF-A) results in the expansion and directed differentiation of endogenous heart progenitors in a mouse myocardial infarction model. VEGF-A modRNA markedly improved heart function and enhanced long-term survival of recipients. This improvement was in part due to mobilization of epicardial progenitor cells and redirection of their differentiation toward cardiovascular cell types. Direct in vivo comparison with DNA vectors and temporal control with VEGF inhibitors revealed the greatly increased efficacy of pulse-like delivery of VEGF-A. Our results suggest that modRNA is a versatile approach for expressing paracrine factors as cell fate switches to control progenitor cell fate and thereby enhance long-term organ repair.
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Genome Sequences of Two Klebsiella pneumoniae Isolates from Different Geographical Regions, Argentina (Strain JHCK1) and the United States (Strain VA360).
Genome Announc
PUBLISHED: 05-04-2013
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We report the sequences of two Klebsiella pneumoniae clinical isolates, strains JHCK1 and VA360, from a newborn with meningitis in Buenos Aires, Argentina, and from a tertiary care medical center in Cleveland, OH, respectively. Both isolates contain one chromosome and at least five plasmids; isolate VA360 contains the Klebsiella pneumoniae carbapenemase (KPC) gene.
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Single-cell and metagenomic analyses indicate a fermentative and saccharolytic lifestyle for members of the OP9 lineage.
Nat Commun
PUBLISHED: 04-13-2013
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OP9 is a yet-uncultivated bacterial lineage found in geothermal systems, petroleum reservoirs, anaerobic digesters and wastewater treatment facilities. Here we use single-cell and metagenome sequencing to obtain two distinct, nearly complete OP9 genomes, one constructed from single cells sorted from hot spring sediments and the other derived from binned metagenomic contigs from an in situ-enriched cellulolytic, thermophilic community. Phylogenomic analyses support the designation of OP9 as a candidate phylum for which we propose the name Atribacteria. Although a plurality of predicted proteins is most similar to those from Firmicutes, the presence of key genes suggests a diderm cell envelope. Metabolic reconstruction from the core genome suggests an anaerobic lifestyle based on sugar fermentation by Embden-Meyerhof glycolysis with production of hydrogen, acetate and ethanol. Putative glycohydrolases and an endoglucanase may enable catabolism of (hemi)cellulose in thermal environments. This study lays a foundation for understanding the physiology and ecological role of the Atribacteria.
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Induction of cell cycle arrest and apoptosis in human osteosarcoma U-2 OS cells by Solanum lyratum extracts.
Nutr Cancer
PUBLISHED: 03-28-2013
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This research focused on a Chinese herb medicine, Solanum lyratum Thunb (Solanaceae) by ethanol extracts (SLE) for investigating the molecular anticancer mechanism in vitro for exploring the means of cell death through the effects on mitochondrial function. We found that SLE induced cytotoxic effects in human osteosacroma U-2 OS cells, and these effects include cell morphological changes, a decrease of the percentage of viable cells and induction of apoptosis. The results suggest that cell death induced by SLE is closely related to apoptosis based on the observations of DAPI staining and sub-G1 phase in U-2 OS cells. Flow cytometric assays also showed that SLE promoted the production of reactive oxygen species and nitric oxide but decreased the levels of mitochondrial membrane potential and promoted the activations of caspase-8 and -9 in U-2 OS cells. SLE inhibited the level of Bcl-2 but promoted the Bax level, and both proteins led to the release of cytochrome c from mitochondria to cytosol and activation of caspase-9 and -3, resulting in the apoptotic death which is mediated through the mitochondrial pathway. Taken together, SLE was demonstrated to be effective in killing U-2 OS osteosacroma cells via the ROS-promoted and mitochondria- and caspase-dependent apoptotic pathways.
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Impact of extracorporeal membrane oxygenation support on clinical outcome of pediatric patients with acute cardiopulmonary failure: a single-center experience.
Biomed J
PUBLISHED: 03-22-2013
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Conventional therapy against acute pediatric cardiopulmonary failure (APCPF) caused by a variety of disease entities remains unsatisfactory with extremely high morbidity and mortality. For refractory APCPF, extracorporeal membrane oxygenation (ECMO) is one of the last resorts.
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Nearly finished genomes produced using gel microdroplet culturing reveal substantial intraspecies genomic diversity within the human microbiome.
Genome Res.
PUBLISHED: 03-14-2013
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The majority of microbial genomic diversity remains unexplored. This is largely due to our inability to culture most microorganisms in isolation, which is a prerequisite for traditional genome sequencing. Single-cell sequencing has allowed researchers to circumvent this limitation. DNA is amplified directly from a single cell using the whole-genome amplification technique of multiple displacement amplification (MDA). However, MDA from a single chromosome copy suffers from amplification bias and a large loss of specificity from even very small amounts of DNA contamination, which makes assembling a genome difficult and completely finishing a genome impossible except in extraordinary circumstances. Gel microdrop cultivation allows culturing of a diverse microbial community and provides hundreds to thousands of genetically identical cells as input for an MDA reaction. We demonstrate the utility of this approach by comparing sequencing results of gel microdroplets and single cells following MDA. Bias is reduced in the MDA reaction and genome sequencing, and assembly is greatly improved when using gel microdroplets. We acquired multiple near-complete genomes for two bacterial species from human oral and stool microbiome samples. A significant amount of genome diversity, including single nucleotide polymorphisms and genome recombination, is discovered. Gel microdroplets offer a powerful and high-throughput technology for assembling whole genomes from complex samples and for probing the pan-genome of naturally occurring populations.
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Driving vascular endothelial cell fate of human multipotent Isl1+ heart progenitors with VEGF modified mRNA.
Cell Res.
PUBLISHED: 03-12-2013
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Distinct families of multipotent heart progenitors play a central role in the generation of diverse cardiac, smooth muscle and endothelial cell lineages during mammalian cardiogenesis. The identification of precise paracrine signals that drive the cell-fate decision of these multipotent progenitors, and the development of novel approaches to deliver these signals in vivo, are critical steps towards unlocking their regenerative therapeutic potential. Herein, we have identified a family of human cardiac endothelial intermediates located in outflow tract of the early human fetal hearts (OFT-ECs), characterized by coexpression of Isl1 and CD144/vWF. By comparing angiocrine factors expressed by the human OFT-ECs and non-cardiac ECs, vascular endothelial growth factor (VEGF)-A was identified as the most abundantly expressed factor, and clonal assays documented its ability to drive endothelial specification of human embryonic stem cell (ESC)-derived Isl1+ progenitors in a VEGF receptor-dependent manner. Human Isl1-ECs (endothelial cells differentiated from hESC-derived ISL1+ progenitors) resemble OFT-ECs in terms of expression of the cardiac endothelial progenitor- and endocardial cell-specific genes, confirming their organ specificity. To determine whether VEGF-A might serve as an in vivo cell-fate switch for human ESC-derived Isl1-ECs, we established a novel approach using chemically modified mRNA as a platform for transient, yet highly efficient expression of paracrine factors in cardiovascular progenitors. Overexpression of VEGF-A promotes not only the endothelial specification but also engraftment, proliferation and survival (reduced apoptosis) of the human Isl1+ progenitors in vivo. The large-scale derivation of cardiac-specific human Isl1-ECs from human pluripotent stem cells, coupled with the ability to drive endothelial specification, engraftment, and survival following transplantation, suggest a novel strategy for vascular regeneration in the heart.
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SOX7 is down-regulated in lung cancer.
J. Exp. Clin. Cancer Res.
PUBLISHED: 03-06-2013
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SOX7 is a transcription factor belonging to the SOX family. Its role in lung cancer is unknown.
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In vitro polyphenolics erythrocyte model and in vivo chicken embryo model revealed gallic acid to be a potential hemorrhage inducer: physicochemical action mechanisms.
Chem. Res. Toxicol.
PUBLISHED: 02-14-2013
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The in vivo chicken embryo model (CEM) demonstrated that gallic acid (GA) induced dysvascularization and hypoxia. Inflammatory edema, Zenkers necrosis, hemolysis, and liposis of cervical muscles were the common symptoms. Levels of the gene hif-1?, HIF-1?, TNF-?, IL-6, and NF?B in cervical muscles were all significantly upregulated, while the vascular endothelial growth factor (VEGF) was downregulated in a dose-responsive manner. Consequently, the cervical muscle inflammation and hemolysis could have been stimulated en route to the tissue TNF-?-canonical and the atypical pathways. We hypothesized that GA could deplete the dissolved oxygen (DO) at the expense of semiquinone and quinone formation, favoring the reactive oxygen species (ROS) production to induce RBC disruption and Fe(2+) ion release. To explore this, the in vitro polyphenolics-erythrocyte model (PEM) was established. PEM revealed that the DO was rapidly depleted, leading to the release of a huge amount of Fe (II) ions and hydrogen peroxide (HPO) in a two-phase kinetic pattern. The kinetic coefficients for Fe (II) ion release ranged from 0.347 h(-1) to 0.774 h(-1); and those for Fe (III) ion production were from 6.66 × 10(-3) h(-1) to 8.93 × 10(-3) h(-1). For phase I HPO production, they ranged from 0.236 h(-1) to 0.774 h(-1) and for phase II HPO production from 0.764 h(-1) to 2.560 h(-1) at GA within 6 ?M to 14 ?M. Thus, evidence obtained from PEM could strongly support the phenomena of CEM. To conclude, GA tends to elicit hypoxia-related inflammation and hemolysis in chicken cervical muscles through its extremely high prooxidant activity.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.