Endoglin potentiates nitric oxide synthesis to enhance definitive hematopoiesis.

During embryonic development, hematopoietic cells develop by a process of endothelial-to hematopoietic transition of a specialized population of endothelial cells. These hemogenic endothelium (HE) cells in turn develop from a primitive population of FLK1(+) mesodermal cells. Endoglin (ENG) is an accessory TGF-β receptor that is enriched on the surface of endothelial and hematopoietic stem cells and is also required for the normal development of hemogenic precursors. However, the functional role of ENG during the transition of FLK1(+) mesoderm to hematopoietic cells is ill defined. To address this we used a murine embryonic stem cell model that has been shown to mirror the temporal emergence of these cells in the embryo. We noted that FLK1(+) mesodermal cells expressing ENG generated fewer blast colony-forming cells but had increased hemogenic potential when compared with ENG non-expressing cells. TIE2(+)/CD117(+) HE cells expressing ENG also showed increased hemogenic potential compared with non-expressing cells. To evaluate whether high ENG expression accelerates hematopoiesis, we generated an inducible ENG expressing ES cell line and forced expression in FLK1(+) mesodermal or TIE2(+)/CD117(+) HE cells. High ENG expression at both stages accelerated the emergence of CD45(+) definitive hematopoietic cells. High ENG expression was associated with increased pSMAD2/eNOS expression and NO synthesis in hemogenic precursors. Inhibition of eNOS blunted the ENG induced increase in definitive hematopoiesis. Taken together, these data show that ENG potentiates the emergence of definitive hematopoietic cells by modulating TGF-β/pSMAD2 signalling and increasing eNOS/NO synthesis.The authors thank Dr Zúñiga-Pflücker (University of Toronto) for the ENG-/- and +/- murine ES cells. This work was supported by grants from the National Health and Medical Research Council of Australia, Australian Research Council and the Dr Tom Bee Stem Cell Research Fund to JEP, Cancer Research UK to VK and GL and the BBSRC, Leukaemia and Lymphoma Research, The Leukaemia and Lymphoma Society, Cancer Research UK, and core support grants by the Wellcome Trust to the Cambridge Institute for Medical Research and Wellcome Trust - MRC Cambridge Stem Cell Institute to BG.This is the final version of the article. It first appeared from the Company of Biologists via http://dx.doi.org/10.1242/​bio.01149

Moral reasoning perspectives of community pharmacists in situations of drug shortages

BACKGROUND: Drug shortages affect health systems worldwide. Research in community pharmacy has focused on the nature, extent and impact of these shortages on patients and pharmacists. However, pharmacists' moral reasoning in situations of drug shortages has not been addressed. OBJECTIVE: To explore the moral reasoning perspectives of Dutch community pharmacists in situations of drug shortages. METHOD: An electronic survey was developed around three drug shortage scenarios with a varying impact on patient outcomes: a Contraceptive, a Parkinson's and an Osteoporosis scenario. Pharmacists rated the likelihood of nine handling options and rated and ranked 13 considerations that may have played a role therein. The considerations represented three moral reasoning perspectives (MRPs): a business orientation (BO), a rules and regulations (RR), and a professional ethics (PE) MRP. Principle component analysis (PCA) was used to investigate construct validity of the MRPs. MRP rating and MRP ranking scores measured the relative importance of the different MRPs of pharmacists in the three shortages. RESULTS: Results from 267 Pharmacists were obtained. They reported mostly similar handling in the three shortages, except for the likelihood to make agreements with prescribers or other pharmacists and regarding the decision to import a product. The PCA analysis confirmed the three MRPs that accounted for 29% of variance in the data. Both the MRP rating and especially the MRP ranking scores indicated that PE-MRP considerations were most influential on pharmacists' intended handling of the shortages. In the Contraceptive and the Osteoporosis scenarios, the relative importance of a BO-MRP was higher than in the Parkinson's scenario. CONCLUSION: Pharmacists predominantly reason with a PE-MRP when handling drug shortages. However, this perspective can be compromised when the drug shortage is perceived to have a lower impact on patient outcomes and when alternative drugs or therapy are expensive

The peculiar kinematics of the multiple populations in the globular cluster Messier 80 (NGC 6093)

We combine MUSE spectroscopy and Hubble Space Telescope ultraviolet (UV) photometry to perform a study of the chemistry and dynamics of the Galactic globular cluster Messier 80 (M80, NGC 6093). Previous studies have revealed three stellar populations that not only vary in their light-element abundances, but also in their radial distributions, with concentration decreasing with increasing nitrogen enrichment. This remarkable trend, which sets M80 apart from the other Galactic globular clusters, points towards a complex formation and evolutionary history. To better understand how M80 formed and evolved, revealing its internal kinematics is key. We find that the most N-enriched population rotates faster than the other two populations at a 2 sigma confidence level. While our data further suggest that the intermediate population shows the least amount of rotation, this trend is rather marginal (1 - 2 sigma). Using axisymmetric Jeans models, we show that these findings can be explained from the radial distributions of the populations if they possess different angular momenta. Our findings suggest that the populations formed with primordial kinematical differences

The epigenetic regulators CBP and p300 facilitate leukemogenesis and represent therapeutic targets in acute myeloid leukemia.

Growing evidence links abnormal epigenetic control to the development of hematological malignancies. Accordingly, inhibition of epigenetic regulators is emerging as a promising therapeutic strategy. The acetylation status of lysine residues in histone tails is one of a number of epigenetic post-translational modifications that alter DNA-templated processes, such as transcription, to facilitate malignant transformation. Although histone deacetylases are already being clinically targeted, the role of histone lysine acetyltransferases (KAT) in malignancy is less well characterized. We chose to study this question in the context of acute myeloid leukemia (AML), where, using in vitro and in vivo genetic ablation and knockdown experiments in murine models, we demonstrate a role for the epigenetic regulators CBP and p300 in the induction and maintenance of AML. Furthermore, using selective small molecule inhibitors of their lysine acetyltransferase activity, we validate CBP/p300 as therapeutic targets in vitro across a wide range of human AML subtypes. We proceed to show that growth retardation occurs through the induction of transcriptional changes that induce apoptosis and cell-cycle arrest in leukemia cells and finally demonstrate the efficacy of the KAT inhibitors in decreasing clonogenic growth of primary AML patient samples. Taken together, these data suggest that CBP/p300 are promising therapeutic targets across multiple subtypes in AML.Funding in the Huntly laboratory comes from Cancer Research UK, Leukemia Lymphoma Research, the Kay Kendal Leukemia Fund, the Leukemia lymphoma Society of America, the Wellcome Trust, The Medical Research Council and an NIHR Cambridge Biomedical Research Centre grant. Patient samples were processed in the Cambridge Blood and Stem Cell Biobank.This is the author accepted manuscript. The final version is available via NPG at http://dx.doi.org/10.1038/onc.2015.9

Bolting and flowering control in sugar beet: relationships and effects of gibberellin, the bolting gene B and vernalization

Using a co-dominant genotypic PCR marker we show for the first time that, in sugar beet, the GA and B-gene pathways are independent for bolt initiation. We show that vernalization permits GA-dependant stem elongation and that the B-allele influences subsequent flowering

GATA2 Promotes Hematopoietic Development and Represses Cardiac Differentiation of Human Mesoderm.

In vertebrates, GATA2 is a master regulator of hematopoiesis and is expressed throughout embryo development and in adult life. Although the essential role of GATA2 in mouse hematopoiesis is well established, its involvement during early human hematopoietic development is not clear. By combining time-controlled overexpression of GATA2 with genetic knockout experiments, we found that GATA2, at the mesoderm specification stage, promotes the generation of hemogenic endothelial progenitors and their further differentiation to hematopoietic progenitor cells, and negatively regulates cardiac differentiation. Surprisingly, genome-wide transcriptional and chromatin immunoprecipitation analysis showed that GATA2 bound to regulatory regions, and repressed the expression of cardiac development-related genes. Moreover, genes important for hematopoietic differentiation were upregulated by GATA2 in a mostly indirect manner. Collectively, our data reveal a hitherto unrecognized role of GATA2 as a repressor of cardiac fates, and highlight the importance of coordinating the specification and repression of alternative cell fates.Ramón y Cajal Program, Spanish Ministry of Economy, Industry, and Competitiveness, Spanish Cancer Association, FERO, Instituto de Salud Carlos III, European Social Fund, MINECO, PERIS Program of the Generalitat de Catalunya, Obra Social la Caixa-Fundacion Josep Carreras, Spanish Institute of Health Carlos III, Wellcome Trust, MRC, CRUK, NIH-NIDD

The endothelial transcription factor ERG promotes vascular stability and growth through Wnt/β-catenin signaling.

Blood vessel stability is essential for embryonic development; in the adult, many diseases are associated with loss of vascular integrity. The ETS transcription factor ERG drives expression of VE-cadherin and controls junctional integrity. We show that constitutive endothelial deletion of ERG (Erg(cEC-KO)) in mice causes embryonic lethality with vascular defects. Inducible endothelial deletion of ERG (Erg(iEC-KO)) results in defective physiological and pathological angiogenesis in the postnatal retina and tumors, with decreased vascular stability. ERG controls the Wnt/β-catenin pathway by promoting β-catenin stability, through signals mediated by VE-cadherin and the Wnt receptor Frizzled-4. Wnt signaling is decreased in ERG-deficient endothelial cells; activation of Wnt signaling with lithium chloride, which stabilizes β-catenin levels, corrects vascular defects in Erg(cEC-KO) embryos. Finally, overexpression of ERG in vivo reduces permeability and increases stability of VEGF-induced blood vessels. These data demonstrate that ERG is an essential regulator of angiogenesis and vascular stability through Wnt signaling.This work was funded by grants from the British Heart Foundation (PG/09/096 and RG/11/17/29256). A.V.S. is a recipient of a National Lung and Heart Institute Foundation Studentship. I.M.A. is a recipient of a DOC-fFORTE fellowship of the Austrian Academy of Sciences at the London Research Institute.This paper was published by Cell Press in Developmental Cell (GM Birdsey, AV Shah, N Dufton, LE Reynolds, LO Almagro, Y Yang, IM Aspalter, ST Khan, JC Mason, E Dejana, B Göttgens, K Hodivala-Dilke, Gerhardt, RH Adams, AM Randi, Developmental Cell 2015, 32, 82-96

Kinematic differences between multiple populations in Galactic globular clusters

Aims. The formation process of multiple populations in globular clusters is still up for debate. These populations are characterized by different light-element abundances. Kinematic differences between the populations are particularly interesting in this respect, because they allow us to distinguish between single-epoch formation scenarios and multi-epoch formation scenarios. We derive rotation and dispersion profiles for 25 globular clusters and aim to find kinematic differences between multiple populations in 21 of them to constrain the formation process. Methods. We split red-giant branch (RGB) stars in each cluster into three populations (P1, P2, P3) for the type-II clusters and two populations (P1 and P2) otherwise using Hubble photometry. We derive the global rotation and dispersion profiles for each cluster by using all stars with radial velocity measurements obtained from MUSE spectroscopy. We also derive these profiles for the individual populations of each cluster. Based on the rotation and dispersion profiles, we calculate the rotation strength in terms of ordered-overrandom motion (v/σ)HL evaluated at the half-light radius of the cluster. We then consistently analyse all clusters for differences in the rotation strength of their populations. Results. We detect rotation in all but four clusters. For NGC 104, NGC 1851, NGC 2808, NGC 5286, NGC 5904, NGC 6093, NGC 6388, NGC 6541, NGC 7078 and NGC 7089 we also detect rotation for P1 and/or P2 stars. For NGC 2808, NGC 6093 and NGC 7078 we find differences in (v/σ)HL between P1 and P2 that are larger than 1σ. Whereas we find that P2 rotates faster than P1 for NGC 6093 and NGC 7078, the opposite is true for NGC 2808. However, even for these three clusters the differences are still of low significance. We find that the strength of rotation of a cluster generally scales with its median relaxation time. For P1 and P2 the corresponding relation is very weak at best. We observe no correlation between the difference in rotation strength between P1 and P2 and cluster relaxation time. The stellar radial velocities derived from MUSE data that this analysis is based on are made publicly available