1,498 research outputs found

    Regulation of Cardiac Progenitors by Combination of Mesp1 and ETS Transcription Factors

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    Heart disease remains the leading cause of death worldwide. By understanding the regulating networks during cardiac development we can exploit those networks to manipulate adult cells into cardiac progenitors and provide an alternative for repairing diseased hearts. Mesp1 is considered to have critical roles during cardiac development but the molecular mechanisms need to be further studied. The roles of ETS transcription factors have been primarily limited to hematopoietic differentiation and cancer progression. The ETS transcription factors are known to have proliferating roles and were hypothesized to also be involved in cardiac differentiation and may potentially be used for cell reprogramming. The first part of this study characterizes the expression pattern of Mesp1 protein in early mouse embryo from E6.5 to E9.5 and provides a full expression profile in differentiating embryoid bodies in vitro from the undifferentiated stage to Day10. Our work showed Mesp1 expresses in the posterior region of E6.5 embryo then starts migrating through the primitive streak toward anterior mesoderm and endoderm in E7.5. A Mesp1 linage tracing ES cell line was established, and it allowed us to trace the Mesp1 derived cell population. The lineage tracing system confirmed Mesp1 expressing cells give rise to a major part of the heart and also contributes to some endodermal derived organs such as the pancreas. The direct DNA binding targets of Mesp1 were determined using a Mesp1 specific antibody to perform ChIP of bound DNA that could then be used in next generation sequencing. The resulting sequence data included cardiac genes such as Gata4, Hand2, and Myocd. Endoderm correlated genes Foxa2, Pitx2, and Gata6 were also shown to be Mesp1 targets. The targeted genes were validated as transcriptional targets using an ES cell line with inducible Mesp1 followed by qPCR of target gene transcript levels with and without Mesp1 expression. Secondly, the complete gene expression profiles of over 20 ETS transcription factors were generated. By comparing the ETS factor expression patterns and identifying which showed cardiac gene activation, ETV4 and ETS2 were chosen for further study of their roles in cardiac differentiation. ETS2 was used in combination with Mesp1 to reprogram Normal Human Dermal Fibroblast into cardiac progenitors. The reprogrammed cells were then characterized for gene expression patterns, surface marker, and structural protein presentation. This work provides thorough insights into the roles of Mesp1 and ETS transcription factors during germ layer development and led to the development of a method to reprogram adult cells into cardiac progenitors that could be applied for clinical use in the future

    Regulation of Cardiac Progenitors by Combination of Mesp1 and ETS Transcription Factors

    Get PDF
    Heart disease remains the leading cause of death worldwide. By understanding the regulating networks during cardiac development we can exploit those networks to manipulate adult cells into cardiac progenitors and provide an alternative for repairing diseased hearts. Mesp1 is considered to have critical roles during cardiac development but the molecular mechanisms need to be further studied. The roles of ETS transcription factors have been primarily limited to hematopoietic differentiation and cancer progression. The ETS transcription factors are known to have proliferating roles and were hypothesized to also be involved in cardiac differentiation and may potentially be used for cell reprogramming. The first part of this study characterizes the expression pattern of Mesp1 protein in early mouse embryo from E6.5 to E9.5 and provides a full expression profile in differentiating embryoid bodies in vitro from the undifferentiated stage to Day10. Our work showed Mesp1 expresses in the posterior region of E6.5 embryo then starts migrating through the primitive streak toward anterior mesoderm and endoderm in E7.5. A Mesp1 linage tracing ES cell line was established, and it allowed us to trace the Mesp1 derived cell population. The lineage tracing system confirmed Mesp1 expressing cells give rise to a major part of the heart and also contributes to some endodermal derived organs such as the pancreas. The direct DNA binding targets of Mesp1 were determined using a Mesp1 specific antibody to perform ChIP of bound DNA that could then be used in next generation sequencing. The resulting sequence data included cardiac genes such as Gata4, Hand2, and Myocd. Endoderm correlated genes Foxa2, Pitx2, and Gata6 were also shown to be Mesp1 targets. The targeted genes were validated as transcriptional targets using an ES cell line with inducible Mesp1 followed by qPCR of target gene transcript levels with and without Mesp1 expression. Secondly, the complete gene expression profiles of over 20 ETS transcription factors were generated. By comparing the ETS factor expression patterns and identifying which showed cardiac gene activation, ETV4 and ETS2 were chosen for further study of their roles in cardiac differentiation. ETS2 was used in combination with Mesp1 to reprogram Normal Human Dermal Fibroblast into cardiac progenitors. The reprogrammed cells were then characterized for gene expression patterns, surface marker, and structural protein presentation. This work provides thorough insights into the roles of Mesp1 and ETS transcription factors during germ layer development and led to the development of a method to reprogram adult cells into cardiac progenitors that could be applied for clinical use in the future

    Regulation of Cardiac Progenitors by Combination of Mesp1 and ETS Transcription Factors

    Get PDF
    Heart disease remains the leading cause of death worldwide. By understanding the regulating networks during cardiac development we can exploit those networks to manipulate adult cells into cardiac progenitors and provide an alternative for repairing diseased hearts. Mesp1 is considered to have critical roles during cardiac development but the molecular mechanisms need to be further studied. The roles of ETS transcription factors have been primarily limited to hematopoietic differentiation and cancer progression. The ETS transcription factors are known to have proliferating roles and were hypothesized to also be involved in cardiac differentiation and may potentially be used for cell reprogramming. The first part of this study characterizes the expression pattern of Mesp1 protein in early mouse embryo from E6.5 to E9.5 and provides a full expression profile in differentiating embryoid bodies in vitro from the undifferentiated stage to Day10. Our work showed Mesp1 expresses in the posterior region of E6.5 embryo then starts migrating through the primitive streak toward anterior mesoderm and endoderm in E7.5. A Mesp1 linage tracing ES cell line was established, and it allowed us to trace the Mesp1 derived cell population. The lineage tracing system confirmed Mesp1 expressing cells give rise to a major part of the heart and also contributes to some endodermal derived organs such as the pancreas. The direct DNA binding targets of Mesp1 were determined using a Mesp1 specific antibody to perform ChIP of bound DNA that could then be used in next generation sequencing. The resulting sequence data included cardiac genes such as Gata4, Hand2, and Myocd. Endoderm correlated genes Foxa2, Pitx2, and Gata6 were also shown to be Mesp1 targets. The targeted genes were validated as transcriptional targets using an ES cell line with inducible Mesp1 followed by qPCR of target gene transcript levels with and without Mesp1 expression. Secondly, the complete gene expression profiles of over 20 ETS transcription factors were generated. By comparing the ETS factor expression patterns and identifying which showed cardiac gene activation, ETV4 and ETS2 were chosen for further study of their roles in cardiac differentiation. ETS2 was used in combination with Mesp1 to reprogram Normal Human Dermal Fibroblast into cardiac progenitors. The reprogrammed cells were then characterized for gene expression patterns, surface marker, and structural protein presentation. This work provides thorough insights into the roles of Mesp1 and ETS transcription factors during germ layer development and led to the development of a method to reprogram adult cells into cardiac progenitors that could be applied for clinical use in the future

    Dose pre-hospital laryngeal mask airway use has a survival benefit in non-shockable cardiac arrest?

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    Background. Whether pre-hospital laryngeal mask airway (LMA) use poses a survival benefit and should be approved as routine airway management in non-shockable cardiac arrest is of major concern. The present study examined the effectiveness of LMA, in comparison to other pre-hospital airway management on individuals who have experienced non-shockable cardiac arrest. Methods. Adult patients who experienced non-shockable cardiac arrest with activation of the emergency medical service (EMS) made up our study cohort in Taoyuan, Taiwan. The data were abstracted from EMS records and cardiac arrest registration protocols. Results. Among the 1912 enrolled patients, most received LMA insertion (72.4%), 108 (5.6%) bag-valve-mask (BVM) ventilation, 376 (19.7%) high-flow oxygen non-rebreather facemask, and only 44 (2.3%) received endotracheal tube intubation (ETI). With regard to survival to discharge, no significant differences in prevalence were evident among the groups: 2.8% of oxygen facial mask, 1.1% of BVM, 2.1% of LMA, and 4.5% of the ETI group survived to discharge (p = 0.314). In comparison to oxygen facial mask use, different types of airway management remained unassociated with survival to discharge after adjusting for variables by logistic regression analysis (BVM: 95% confidence interval [CI], 0.079 – 1.639 [p = 0.186]; LMA: 95% CI, 0.220–2.487 [p = 0.627]; ETI: 95% CI, 0.325–17.820 [p = 0.390]). The results of Hosmer-Lemeshow goodness-of-fit test of logistic regression model revealed good calibration. Conclusions. Pre-hospital LMA use was not associated with additional survival to discharge compared with facial oxygen mask, BVM, or ETI following non-shockable cardiac arrest

    An iPS-derived in vitro model of human atrial conduction

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    Atrial fibrillation (AF) is the most common arrhythmia in the United States, affecting approximately 1 in 10 adults, and its prevalence is expected to rise as the population ages. Treatment options for AF are limited; moreover, the development of new treatments is hindered by limited (1) knowledge regarding human atrial electrophysiological endpoints (e.g., conduction velocity [CV]) and (2) accurate experimental models. Here, we measured the CV and refractory period, and subsequently calculated the conduction wavelength, in vivo (four subjects with AF and four controls), and ex vivo (atrial slices from human hearts). Then, we created an in vitro model of human atrial conduction using induced pluripotent stem (iPS) cells. This model consisted of iPS-derived human atrial cardiomyocytes plated onto a micropatterned linear 1D spiral design of Matrigel. The CV (34-41 cm/s) of the in vitro model was nearly five times faster than 2D controls (7-9 cm/s) and similar to in vivo (40-64 cm/s) and ex vivo (28-51 cm/s) measurements. Our iPS-derived in vitro model recapitulates key features of in vivo atrial conduction and may be a useful methodology to enhance our understanding of AF and model patient-specific disease

    Excavatoids O and P, New 12-Hydroxybriaranes from the Octocoral Briareum excavatum

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    Two new 12-hydroxybriarane diterpenoids, designated as excavatoids O (1) and P (2), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1 and 2 were established on the basis of extensive spectral data analysis. Excavatoid P (2) is the first metabolite which possesses a 6β -chlorine atom in briarane analogues

    Detection of Cartilage Oligomeric Matrix Protein Using a Quartz Crystal Microbalance

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    Current methods for diagnosing early stage osteoarthritis (OA) based on the magnetic resonance imaging and enzyme-linked immunosorbent assay methods are specific, but require specialized laboratory facilities and highly trained personal to obtain a definitive result. In this work, a user friendly and non-invasive quartz crystal microbalance (QCM) immunosensor method has been developed to detect Cartilage Oligomeric Matrix Protein (COMP) for early stage OA diagnosis. This QCM immunosensor was fabricated to immobilize COMP antibodies utilizing the self-assembled monolayer technique. The surface properties of the immunosensor were characterized by its FTIR and electrochemical impedance spectra (EIS). The feasibility study was based on urine samples obtained from 41 volunteers. Experiments were carried out in a flow system and the reproducibility of the electrodes was evaluated by the impedance measured by EIS. Its potential dynamically monitored the immunoreaction processes and could increase the efficiency and sensitivity of COMP detection in laboratory-cultured preparations and clinical samples. The frequency responses of the QCM immunosensor changed from 6 kHz when testing 50 ng/mL COMP concentration. The linear regression equation of frequency shift and COMP concentration was determined as: y = 0.0872 x + 1.2138 (R2 = 0.9957). The COMP in urine was also determined by both QCM and EIS for comparison. A highly sensitive, user friendly and cost effective analytical method for the early stage OA diagnosis has thus been successfully developed

    Transcription factors ETS2 and MESP1 transdifferentiate human dermal fibroblasts into cardiac progenitors

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    Unique insights for the reprograming of cell lineages have come from embryonic development in the ascidian Ciona, which is dependent upon the transcription factors Ci-ets1/2 and Ci-mesp to generate cardiac progenitors. We tested the idea that mammalian v-ets erythroblastosis virus E26 oncogene homolog 2 (ETS2) and mesoderm posterior (MESP) homolog may be used to convert human dermal fibroblasts into cardiac progenitors. Here we show that murine ETS2 has a critical role in directing cardiac progenitors during cardiopoiesis in embryonic stem cells. We then use lentivirus-mediated forced expression of human ETS2 to convert normal human dermal fibroblasts into replicative cells expressing the cardiac mesoderm marker KDR(+). However, although neither ETS2 nor the purported cardiac master regulator MESP1 can by themselves generate cardiac progenitors de novo from fibroblasts, forced coexpression of ETS2 and MESP1 or cell treatment with purified proteins reprograms fibroblasts into cardiac progenitors, as shown by the de novo appearance of core cardiac transcription factors, Ca(2+) transients, and sarcomeres. Our data indicate that ETS2 and MESP1 play important roles in a genetic network that governs cardiopoiesis

    Semiconductor Quantum Dots for Biomedicial Applications

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    Semiconductor quantum dots (QDs) are nanometre-scale crystals, which have unique photophysical properties, such as size-dependent optical properties, high fluorescence quantum yields, and excellent stability against photobleaching. These properties enable QDs as the promising optical labels for the biological applications, such as multiplexed analysis of immunocomplexes or DNA hybridization processes, cell sorting and tracing, in vivo imaging and diagnostics in biomedicine. Meanwhile, QDs can be used as labels for the electrochemical detection of DNA or proteins. This article reviews the synthesis and toxicity of QDs and their optical and electrochemical bioanalytical applications. Especially the application of QDs in biomedicine such as delivering, cell targeting and imaging for cancer research, and in vivo photodynamic therapy (PDT) of cancer are briefly discussed
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