Search results for "vitamin K"
showing 10 items of 108 documents
e-Health-based management of patients receiving oral anticoagulation therapy: results from the observational thrombEVAL study
2017
Essentials e-Health based health care by an expert centre may advance management of oral anticoagulation. Outcome of patients was compared between an e-health based coagulation service and regular care. Patients in the coagulation service cohort experienced a significantly better clinical outcome. Lower risk for adverse events was related to anticoagulation-specific and non-specific outcome. SummaryBackground Management of oral anticoagulation (OAC) therapy is essential to minimize adverse events in patients receiving vitamin K-antagonists (VKAs). Data on the effect of e-health-based anticoagulation management systems on the clinical outcome of OAC patients are limited. Objectives To compar…
Subtherapeutic Anticoagulation Control under Treatment with Vitamin K-Antagonists—Data from a Specialized Coagulation Service
2019
AbstractIn contrast to overanticoagulation, evidence on risk factors and outcome of subtherapeutic oral anticoagulation (OAC) with vitamin K-antagonists (VKAs) under optimum care is limited. We investigated the clinical phenotype, anticoagulation control, and clinical outcome of 760 VKA patients who received OAC therapy by a specialized coagulation service in the thrombEVAL study (NCT01809015). During 281,934 treatment days, 278 patients experience ≥ 1 episode of subtherapeutic anticoagulation control and had lower quality of OAC therapy compared to 482 patients without subtherapeutic international normalized ratio: 67.6%, interquartile range (IQR) 54.9%/76.8% versus 81.0%, IQR 68.5%/90.4%;…
Antimutagenic effects and possible mechanisms of action of vitamins and related compounds against genotoxic heterocyclic amines from cooked food.
1999
Possible antimutagenic activity of 26 vitamins and related compounds - ascorbic acid, beta-carotene, cyanocobalamin, folic acid, nicotinic acid, nicotinamide, pantothenic acid, pyridoxale, pyridoxamine, pyridoxine, retinal, retinol, retinoic acid, retinyl acetate, retinyl palmitate, riboflavin, riboflavin 5'-phosphate, flavin adenine dinucleotide (FAD), alpha-tocopherol, alpha-tocopherol acetate, vitamins K(1), K(3), K(4), 1, 4-naphthoquinone, and coenzyme Q(10) - was tested against six heterocyclic amine (HCA) mutagens, i.e., 2-amino-3-methyl-imidazo[4, 5-f]quinoline (IQ), 2-amino-3,4-dimethyl-imidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethyl-imidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1…
Vitamin K epoxide reductase activity in the metabolism of epoxides
1985
Abstract The importance of vitamine K epoxide reductase for the metabolism of a range of structurally diverse epoxides has been investigated. Vitamin K 1 epoxide is reduced by rat liver microsomes at a rate of 0.47 nmoles/g liver/min. The rate of menadione oxide reduction is not significantly higher than the non-enzymatic reduction rate. No measurable reduction of benzo[ a ]pyrene 4,5-oxide, benzo[ a ]pyrene 7,8-oxide, phenanthrene 9,10-oxide, styrene 7,8-oxide, and dieldrin has been detected, nor could trichothecene T-2 toxin inhibit reduction of vitamin K 1 epoxide. Thus, vitamin K epoxide reductase is very specific for vitamin K 1 epoxide. Taking into account the range of structurally di…
Choice of New Oral Anticoagulant Agents Versus Vitamin K Antagonists in Atrial Fibrillation: FANTASIIA Study.
2015
Introduction: Atrial fibrillation (AF) is associated with an increased risk of thromboembolic events. Many patients with AF receive chronic anticoagulation, either with vitamin K antagonists (VKAs) or with non-VKA oral anticoagulants (NOACs). We sought to analyze variables associated with prescription of NOAC. Methods: Patients with AF under anticoagulation treatment were prospectively recruited in this observational registry. The sample comprised 1290 patients under chronic anticoagulation for AF, 994 received VKA (77.1%) and 296 NOAC (22.9%). Univariate and multivariate analyses were performed to identify variables associated with use of NOAC. Results: Mean age was 73.8 ± 9.4 years, and 4…
Antithrombotic Therapy in Patients with Atrial Fibrillation and Acute Coronary Syndrome Treated Medically or with Percutaneous Coronary Intervention …
2019
Background: The safety and efficacy of antithrombotic regimens may differ between patients with atrial fibrillation who have acute coronary syndromes (ACS), treated medically or with percutaneous coronary intervention (PCI), and those undergoing elective PCI. Methods: Using a 2×2 factorial design, we compared apixaban with vitamin K antagonists and aspirin with placebo in patients with atrial fibrillation who had ACS or were undergoing PCI and were receiving a P2Y 12 inhibitor. We explored bleeding, death and hospitalization, as well as death and ischemic events, by antithrombotic strategy in 3 prespecified subgroups: patients with ACS treated medically, patients with ACS treated with PCI,…
Effects of β-Carotene, Retinal, Riboflavin, α-Tocopherol and Vitamins C and K1 on Sister-chromatid Exchanges Induced by 3-Amino-1-methyl-5H-pyrido[4,…
1998
The vitamins and related compounds cited in the title were investigated for their abilities to modulate sister-chromatid exchanges (SCEs) induced by Trp-P-2 or cyclophosphamide (CP) in human peripheral lymphocyte cultures in the presence of an exogenous metabolizing system from rat liver. When inducer and test substances were given simultaneously, beta-carotene, retinal and alpha-tocopherol caused a dose-dependent decrease of SCE frequencies induced by Trp-P-2 and CP. Vitamin K1, however, brought about an identical effect with Trp-P-2 only, while with CP an initial decrease of SCEs was followed by a statistically significant re-increase at higher concentrations. Vitamin C was ineffective ag…
Dosing issues with non-vitamin K antagonist oral anticoagulants for the treatment of non-valvular atrial fibrillation: Why we should not underdose ou…
2018
Summary Non-vitamin K antagonist oral anticoagulants (NOACs) – dabigatran, rivaroxaban, apixaban and edoxaban – are well established in terms of preventing stroke or systemic embolism in patients with non-valvular atrial fibrillation and high thromboembolism risk. When prescribed incorrectly, NOACs are associated with an increased risk of ischaemic events and bleeding. Current NOAC labels explicitly address dose adjustments according to age, body weight, renal function and concomitant treatment with P-glycoprotein inhibitors. The required dose adjustments vary significantly from molecule to molecule, thereby creating a complex dose adjustment environment. Furthermore, recommendations suppor…
International Normalized Ratio and Mortality Risk in Acute Heart Failure and Nonvalvular Atrial Fibrillation Patients Receiving Vitamin K Antagonists
2019
Introduction and objectives: Heart failure patients with nonvalvular atrial fibrillation (NVAF) on treatment with vitamin K antagonists (VKA) often have suboptimal international normalized ratio (INR) values. Our aim was to evaluate the association between INR values at admission due to acute heart failure and mortality risk during follow-up. Methods: In this observational study, we retrospectively assessed INR on admission in 1137 consecutive patients with acute heart failure and NVAF who were receiving VKA treatment. INR was categorized into optimal values (INR = 2-3, n = 210), subtherapeutic (INR 3, n = 267). Because INR did not meet the proportional hazards assumption for mortality, res…
Antithrombotic Therapy after Acute Coronary Syndrome or PCI in Atrial Fibrillation
2019
Background: Appropriate antithrombotic regimens for patients with atrial fibrillation who have an acute coronary syndrome or have undergone percutaneous coronary intervention (PCI) are unclear. Methods: In an international trial with a two-by-two factorial design, we randomly assigned patients with atrial fibrillation who had an acute coronary syndrome or had undergone PCI and were planning to take a P2Y12 inhibitor to receive apixaban or a vitamin K antagonist and to receive aspirin or matching placebo for 6 months. The primary outcome was major or clinically relevant nonmajor bleeding. Secondary outcomes included death or hospitalization and a composite of ischemic events. Results: Enroll…