Studies on the Isolation of Messenger RNA

The rapidly-labeled RNA fraction of E. coli has been purified approximately 15-fold on benzoylated DEAE cellulose columns (BC). It is metabolically unstable (as shown by a pulse/chase experiment) and is considered to represent mRNA. The yield of pulse-labeled RNA is about 70% and comprises 4-5% of the RNA of the cell. The true size distribution of this RNA, determined by sedimentation in a denaturing solvent (99% DMSO), does not change during purification. This result indicates that neither degradation nor selection for molecules of a particular size has occurred. Upon sedimentation of the final preparation in DMSO, the distribution of pulse label is the same as that of RNA mass, indicating nearly complete separation from longer-lived RNA components. The isolation of globin-specific mRNA from rabbit reticulocytes has been attempted, both by a modification of BC chromatography and by the previously published sucrose gradient method of Marbaix, Burny, and Chantrenne, but the results (in both cases) were inconclusive. The final preparation sedimented heterogeneously, with an estimated mean sedimentation coefficient (s20,w) of 8.4 S. Tests of the possible identity of this material as mRNA by biological assay in a cell-free protein synthesizing system have not been attempted.</p

The year in cardiology: heart failure

No abstract available

Statin use in cancer survivors versus the general population: cohort study using primary care data from the UK clinical practice research datalink.

BACKGROUND: Cancer survivors may be at increased risk of cardiovascular diseases, but little is known about whether prescribing guidelines for the primary prevention of cardiovascular disease are adequately implemented in these patients. We compared levels of statin initiation and cessation among cancer survivors compared to the general population to determine differences in uptake of pharmaceutical cardiovascular risk prevention measures in these groups. METHODS: The study population included individuals aged ≥40 during 2005-13 within the UK Clinical Practice Research Datalink primary care database. Within this population we identified cancer survivors who were alive and under follow-up at least 1 year after diagnosis, and controls with no cancer history. Follow-up time prior to cancer diagnosis was included in the control cohort. Using logistic regression, we compared these groups with respect to uptake of statins within 1 month of a first high recorded cardiovascular risk score. Then, we used Cox modelling to compare persistence on statin therapy (time to statin cessation) between cancer survivors and controls from the main study population who had initiated on a statin. RESULTS: Among 4202 cancer survivors and 113,035 controls with a record indicating a high cardiovascular risk score, 23.0% and 23.5% respectively initiated a statin within 1 month (adjusted odds ratio 0.98 [91.8-1.05], p = 0.626). Cancer survivors appeared more likely to discontinue statin treatment than controls (adjusted hazard ratio 1.07 [1.01-1.12], p = 0.02). This greater risk of discontinuing was only evident after the first year of therapy (p-interaction < 0.001). INTERPRETATION: Although cardiovascular risk is thought to be higher in cancer survivors compared to the general population, cancer survivors were no more likely to receive statins, and marginally more likely to cease long-term therapy, than general population controls. There may be an opportunity to mitigate the suspected higher cardiovascular risk in the growing population of cancer survivors by improving uptake of lipid-lowering treatment and persistence on therapy

Simulations of magnetic Bragg scattering in transmission electron microscopy

We have simulated the magnetic Bragg scattering in transmission electron microscopy in two antiferromagnetic compounds, NiO and LaMnAsO. This weak magnetic phenomenon was observed in NiO experimentally by Loudon. We have computationally reproduced Loudon's experimental data, and for comparison we have performed calculations for the LaMnAsO compound as a more challenging case, containing lower concentration of magnetic elements and strongly scattering heavier non-magnetic elements. We have also described thickness and voltage dependence of the intensity of the antiferromagnetic Bragg spot for both compounds. We have employed two computational approaches, one assuming a static lattice with Debye-Waller smeared potentials, and another explicitly considering the atomic vibrations within the quantum excitations of phonons model (thermal diffuse scattering). The structural analysis shows that the antiferromagnetic Bragg spot appears in between (111) and (000) reflections for NiO, while for LaMnAsO the antiferromagnetic Bragg spot appears at the position of the (110) reflection in the diffraction pattern, which corresponds to a forbidden reflection of the crystal structure. Calculations predict that the intensity of the magnetic Bragg spot in NiO is significantly stronger than thermal diffuse scattering at room temperature. For LaMnAsO, the magnetic Bragg spot is weaker than the room-temperature thermal diffuse scattering, but its detection can be facilitated at reduced temperatures

The Journal of the Friends' Historical Society vol. 4 No. 3

1. Notices. 2. Notes and Queries. 3. Visits of American Ministers to Europe. 4. A Prophecy of Toleration. 5. Presentations of Quakers in Episcopal Visitations, 1662-1679. 6. Editors' Notes. 7. Episodes in the Life of May Drummond II. 8. Review of Hancock's "Peculium". 9. The Wilkinson and Story Controversy in Bristol. 10. Service in Sackcloth. 11. Present State of the Nonconformists. 12. A Vision seen by George Fox. 13. Friends in Current Literature. 14. George Fox and the Durham College