Vitamin K status, supplementation and vascular disease: a systematic review and meta-analysis

Objectives: Vascular stiffness (VS) and vascular calcification (VC) are surrogate markers of vascular health associated with cardiovascular events. Vitamin K-dependent proteins (VKDP) are associated with VS and VC and require vitamin K for activity. We conducted a systematic review and meta-analysis of: (1) the effect of vitamin K supplementation on VS and VC and (2) association of inactive VKDP levels with incident cardiovascular disease and mortality. Methods: Two authors searched MEDLINE and Embase databases and Cochrane and ISRCTN registries for studies of vitamin K clinical trials that measured effects on VC, VS or VKDP and longitudinal studies assessing effect of VKDP on incident CVD or mortality. Random effects meta-analyses were performed. Results: Thirteen controlled clinical trials (n=2162) and 14 longitudinal studies (n=10 726) met prespecified inclusion criteria. Vitamin K supplementation was associated with significant reduction in VC (−9.1% (95% CI −17.7 to −0.5); p=0.04) and VKDP (desphospho-uncarboxylated matrix Gla protein; −44.7% (95% CI −65.1 to −24.3), p<0.0001) and uncarboxylated osteocalcin; −12.0% (95% CI −16.7 to −7.2), p<0.0001) compared with control, with a non-significant improvement in VS. In longitudinal studies with median follow-up of 7.8 (IQR 4.9–11.3) years, VKDP levels were associated with a combined endpoint of CVD or mortality (HR 0.45 (95% CI 0.07 to 0.83), p=0.02). Conclusions: Supplementation with vitamin K significantly reduced VC, but not VS, compared with control. The conclusions drawn are limited by small numbers of studies with substantial heterogeneity. VKDP was associated with combined endpoint of CVD or mortality. Larger clinical trials of effect of vitamin K supplementation to improve VC, VS and long-term cardiovascular health are warranted. Trial registration number: CRD42017060344

Who takes risks in high-risk sport? The role of alexithymia

People who have difficulty identifying and describing their emotions are more likely to seek out the experience of emotions in the high-risk domain. This is because the high-risk domain provides the experience of more easily identifiable emotions (e.g., fear). However, the continued search for intense emotion may lead such individuals to take further risks within this domain, which in turn would lead to a greater likelihood of experiencing accidents. Across three studies, we provide the first evidence in support of this view. In Study 1 (n = 762) alexithymia was associated with greater risk taking and a greater propensity to experience accidents and close calls. In Study 2 (n = 332) and Study 3 (n = 356) additional bootstrapped mediation models confirmed these relationships. The predictive role of alexithymia remained significant when controlling for sensation seeking (Study 1) and anhedonia (Study 2 and Study 3). We discuss the practical implications of the present model as they pertain to minimizing accidents and close calls in the high risk domain

Guidance for Restarting Inflammatory Bowel Disease Therapy in Patients Who Withheld Immunosuppressant Medications During COVID-19

Patients with inflammatory bowel diseases [IBD] are frequently treated with immunosuppressant medications. During the coronavirus disease 2019 [COVID-19] pandemic, recommendations for IBD management have included that patients should stay on their immunosuppressant medications if they are not infected with the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], but to temporarily hold these medications if symptomatic with COVID-19 or asymptomatic but have tested positive for SARS-CoV-2. As more IBD patients are infected globally, it is important to also understand how to manage IBD medications during convalescence while an individual with IBD is recovering from COVID-19. In this review, we address the differences between a test-based versus a symptoms-based strategy as related to COVID-19, and offer recommendations on when it is appropriate to consider restarting IBD therapy in patients testing positive for SARS-CoV-2 or with clinical symptoms consistent with COVID-19. In general, we recommend a symptoms-based approach, due to the current lack of confidence in the accuracy of available testing and the clinical significance of prolonged detection of virus via molecular testing

Books

New BMJ ABC seriesABC of Spinal Cord Injury. 2nd ed. By D. Grundy and A Swain. Pp. 61. Illustrated. £11 London: BMJ 1993.ABC of Diabetes. 3rd ed. By Peter J. Watkins Pp. 56. Illustrated. London: BM]. 1993. Obtainable from IJbriger Book Distributors, Bloemfontein.ABC of Transfusion. 2nd ed. Ed by Marcela A. Contreras. Pp. 66. £14,50. London: BM]. 1993.ABC of Vascular Diseases. Ed by John H. N. Wolfe. Pp. 79. London: BM]. 1993.Female sterilisation Female Sterilization: A Guide to Provision of Services. Pp. x + 197. illustrated. Sfr. 41. Geneva: WHO. 1992.Cervical cancer Cervical Cancer Screening Programmes: Managerial Guidelines. By A. B. Miller. Pp. viii + 50. SFr.12. Geneva: WHO. 1992.Alcohol in southern Africa Liquor and Labor in Southern Africa. Ed by Jonathan Crush and Charles Ambler. Pp. 432. R99. Pietermaritzburg: Universiry of Tatal Press. 1992.Primary care in AIDS Primary AIDS Care. By Clive Evian. Pp. 267. Illustrated. R59,95. Joha=esburg: Jacana. 1993.Kliniese etiek Kliniese Etiek: 'n Christelike Benadering. 2de uitg. Deur Uys en Smit. Pp. 166. Kenwyn: Juta. 1992.Ovarian carcinoma Cancer of the Ovary. Ed by Maurice Markman and William J. Hoskins. Pp. xv + 442. Illustrated. $156,50. New York: Raven Press. 1992.Complications of cirrhosis Bailliere's Clinical Gastroenterology. International Practice and Research: Portal Hypertension. Ed by R. Shields. Pp. 208. Illustrated. £27,50. Kent: Harcourt Brace Jovanovich. 1992.Treating diarrhoea Readings on Diarrhoea. Pp. vi + 147. Illustrated. Sfr. 20. Geneva: WHO. 1992.Manual of arthroscopy Techniques in Therapeutic Arthroscopy. Ed by J. Serge Parisien. Pp. 385. Illustrated.$157,50. New York: Raven Press. 1993.Chemicals and birth defects Chemically Induced Birth Defects. 2nd ed. By James L. Schardein. Pp. xiv + 902. $250. New York: Marcel Dekker 1993.Virology Progress in Medical Virology. Vol. 40. Ed by J. L. Melnick. Pp. viii + 221. Illustrated. Sfr. 265. Basel: S. Karger. 1993.Perfused liver Perfused Liver: Clinical and Basic Applications. Ed by F. Ballet and R. G. Thurrnan. Pp. 398. Illustrated. £46. London: John Libbey. 1991

Acute Hepatitis C Virus in an HIV Clinic: A Screening Strategy, Risk Factors, and Perception of Risk

Abstract Acute hepatitis C virus (HCV) infection is being acquired undetected among HIV-infected individuals. A practical way to regularly screen HIV-infected patients for acute HCV irrespective of perceived risk or symptoms is needed. We piloted implementation of an acute HCV screening strategy using routine HIV clinical care schedules and the least costly blood tests, in a Rhode Island HIV care center. Study participants had ongoing HCV risk, completed questionnaires encompassing risk behaviors and perception of risk, and were screened with quarterly alanine aminotransferase (ALT). ALT rise triggered HCV RNA testing, with pooled rather than individual specimen HCV RNA testing for underinsured participants. Participants were primarily older, collegeeducated men who have sex with men (MSM) with history of sexually transmitted infection other than HIV. One of 58 participants developed acute HCV in 50 person-years of observation for an annual incidence of 2.0% per year (95% confidence interval [CI] 0.05-11.1%). The majority (54%) of MSM did not perceive that traumatic sexual and drug practices they were engaging in put them at risk for HCV. Unprotected sex often occurred under the influence of drugs or alcohol. Self-reported HCV risk and participation in several risk behaviors declined during the study. It was possible to collect frequent ALTs in a busy HIV clinic with 71% of total projected ALTs obtained and 88% of participants having at least one ALT during the 9-month follow-up period. All instances of ALT rise led to reflexive HCV RNA testing. Tracking quarterly ALT for elevation to systematically prompt HCV RNA testing before seroconversion is a promising approach to screen for acute HCV in a real-world HIV clinical setting

Deterministic delivery of externally cold and precisely positioned single molecular ions

We present the preparation and deterministic delivery of a selectable number of externally cold molecular ions. A laser cooled ensemble of Mg^+ ions subsequently confined in several linear Paul traps inter-connected via a quadrupole guide serves as a cold bath for a single or up to a few hundred molecular ions. Sympathetic cooling embeds the molecular ions in the crystalline structure. MgH^+ ions, that serve as a model system for a large variety of other possible molecular ions, are cooled down close to the Doppler limit and are positioned with an accuracy of one micrometer. After the production process, severely compromising the vacuum conditions, the molecular ion is efficiently transfered into nearly background-free environment. The transfer of a molecular ion between different traps as well as the control of the molecular ions in the traps is demonstrated. Schemes, optimized for the transfer of a specific number of ions, are realized and their efficiencies are evaluated. This versatile source applicable for broad charge-to-mass ratios of externally cold and precisely positioned molecular ions can serve as a container-free target preparation device well suited for diffraction or spectroscopic measurements on individual molecular ions at high repetition rates (kHz).Comment: 11 pages, 8 figure

Automated Coronal Hole Detection using Local Intensity Thresholding Techniques

We identify coronal holes using a histogram-based intensity thresholding technique and compare their properties to fast solar wind streams at three different points in the heliosphere. The thresholding technique was tested on EUV and X-ray images obtained using instruments onboard STEREO, SOHO and Hinode. The full-disk images were transformed into Lambert equal-area projection maps and partitioned into a series of overlapping sub-images from which local histograms were extracted. The histograms were used to determine the threshold for the low intensity regions, which were then classified as coronal holes or filaments using magnetograms from the SOHO/MDI. For all three instruments, the local thresholding algorithm was found to successfully determine coronal hole boundaries in a consistent manner. Coronal hole properties extracted using the segmentation algorithm were then compared with in situ measurements of the solar wind at 1 AU from ACE and STEREO. Our results indicate that flux tubes rooted in coronal holes expand super-radially within 1 AU and that larger (smaller) coronal holes result in longer (shorter) duration high-speed solar wind streams

Search For Trapped Antihydrogen

We present the results of an experiment to search for trapped antihydrogen atoms with the ALPHA antihydrogen trap at the CERN Antiproton Decelerator. Sensitive diagnostics of the temperatures, sizes, and densities of the trapped antiproton and positron plasmas have been developed, which in turn permitted development of techniques to precisely and reproducibly control the initial experimental parameters. The use of a position-sensitive annihilation vertex detector, together with the capability of controllably quenching the superconducting magnetic minimum trap, enabled us to carry out a high-sensitivity and low-background search for trapped synthesised antihydrogen atoms. We aim to identify the annihilations of antihydrogen atoms held for at least 130 ms in the trap before being released over ~30 ms. After a three-week experimental run in 2009 involving mixing of 10^7 antiprotons with 1.3 10^9 positrons to produce 6 10^5 antihydrogen atoms, we have identified six antiproton annihilation events that are consistent with the release of trapped antihydrogen. The cosmic ray background, estimated to contribute 0.14 counts, is incompatible with this observation at a significance of 5.6 sigma. Extensive simulations predict that an alternative source of annihilations, the escape of mirror-trapped antiprotons, is highly unlikely, though this possibility has not yet been ruled out experimentally.Comment: 12 pages, 7 figure

Apparatus for a Search for T-violating Muon Polarization in Stopped-Kaon Decays

The detector built at KEK to search for T-violating transverse muon polarization in K+ --> pi0 mu+ nu (Kmu3) decay of stopped kaons is described. Sensitivity to the transverse polarization component is obtained from reconstruction of the decay plane by tracking the mu+ through a toroidal spectrometer and detecting the pi0 in a segmented CsI(Tl) photon calorimeter. The muon polarization was obtained from the decay positron asymmetry of muons stopped in a polarimeter. The detector included features which minimized systematic errors while maintaining high acceptance.Comment: 56 pages, 30 figures, submitted to NI

A Helicity-Based Method to Infer the CME Magnetic Field Magnitude in Sun and Geospace: Generalization and Extension to Sun-Like and M-Dwarf Stars and Implications for Exoplanet Habitability

Patsourakos et al. (Astrophys. J. 817, 14, 2016) and Patsourakos and Georgoulis (Astron. Astrophys. 595, A121, 2016) introduced a method to infer the axial magnetic field in flux-rope coronal mass ejections (CMEs) in the solar corona and farther away in the interplanetary medium. The method, based on the conservation principle of magnetic helicity, uses the relative magnetic helicity of the solar source region as input estimates, along with the radius and length of the corresponding CME flux rope. The method was initially applied to cylindrical force-free flux ropes, with encouraging results. We hereby extend our framework along two distinct lines. First, we generalize our formalism to several possible flux-rope configurations (linear and nonlinear force-free, non-force-free, spheromak, and torus) to investigate the dependence of the resulting CME axial magnetic field on input parameters and the employed flux-rope configuration. Second, we generalize our framework to both Sun-like and active M-dwarf stars hosting superflares. In a qualitative sense, we find that Earth may not experience severe atmosphere-eroding magnetospheric compression even for eruptive solar superflares with energies ~ 10^4 times higher than those of the largest Geostationary Operational Environmental Satellite (GOES) X-class flares currently observed. In addition, the two recently discovered exoplanets with the highest Earth-similarity index, Kepler 438b and Proxima b, seem to lie in the prohibitive zone of atmospheric erosion due to interplanetary CMEs (ICMEs), except when they possess planetary magnetic fields that are much higher than that of Earth.Comment: http://adsabs.harvard.edu/abs/2017SoPh..292...89