The aim of this contribution was to check if adsorptive stripping differential pulse voltammetry (AdSDPV) is suitable tool for sensitive simultenous electrochemical detection of lipophilic vitamins. Retinol (vitamin A1), cholecalciferol (vitamin D3), α-tocopherol (vitamin E) and phylloquinone (vitamin K1) were selected as representatives. All electrochemical measurements were performed in two s...

Difenacoum, an antivitamin K anticoagulant, has been widely used as rodenticide to manage populations of rodents. Difenacoum belongs to the second generation of anticoagulant, and, as all the molecules belonging to the second generation of anticoagulant, difenacoum is often involved in primary poisonings of domestic animals and secondary poisonings of wildlife by feeding contaminated rodents. T...

Cetuximab is an immunoglobulin G1 monoclonal antibody that binds to the extracellular domain of the epidermal growth factor receptor (EGFR) blocking ligand-induced auto-phosphorylation and subsequent receptor mediated signalling.1,2 Cetuximab in combination with chemotherapy is effective in the treatment of EGFR-expressing tumors including metastatic colorectal cancer (mCRC).2,3 EGFR is strongl...

phylloquinone (vitamin K1) versus menaquinones (vitamins K2), and their relative contribution in meeting the needs for vitamin K, not only for the synthesis of the hepatic coagulation factors but also for the less well understood vitamin K-dependent carboxylation reactions in other tissues such as bone. Largely unanswered questions surround the comparative intermediary metabolism and transport ...

The vitamin K-dependent carboxylating system has been solubilized by Lubrol PX or Triton X-100 treatment of vitamin K-deficient rat liver microsomes. As obtained from vitamin K-deficient rat liver, this soluble preparation is dependent upon the in vitro addition of vitamin K1 for carboxylating activity. The enzyme system is complex and is dependent upon NADH and dithiothreitol for maximum activ...

The triage theory posits that some functions of micronutrients (the ’40 essential vitamins, minerals, fatty acids, and amino acids) are restricted during shortage and that functions required for short-term survival take precedence over those that are less essential. Insidious changes accumulate as a consequence of restriction, which increases the risk of diseases of aging. For 16 known vitamin ...

A practical synthesis of menaquinone-7 (MK-7, vitamin K2) in the all-trans form was designed. Stereoselective synthesis of MK-7 was achieved through a “1 + 6” convergent strategy by condensation of two building blocks, menadione monoprenyl derivative (fragment “1”) with hexaprenyl bromide (fragment “6”, 82%). Pd-catalyzed desulfonation with LiEt3BH (78%) was followed by oxidation of the hydroqu...

The intramembrane vitamin K epoxide reductase (VKOR) supports blood coagulation in humans and is the target of the anticoagulant warfarin. VKOR and its homologues generate disulphide bonds in organisms ranging from bacteria to humans. Here, to better understand the mechanism of VKOR catalysis, we report two crystal structures of a bacterial VKOR captured in different reaction states. These stru...

BACKGROUND Blood anticoagulation after heart valve replacement is a recognized difficulty all over the world. In this study, we identified the effect of amiodarone on the function of warfarin and confirmed the countermeasure by concluding the genotype distribution of vitamin K epoxide reductase complex 1 (VKORC1) and cytochrome P450 2C9 (CYP2C9) of the patient to predict the security dose of wa...

Previously we reported that we could increase the fraction of carboxylated factor X by reducing the affinity of the propeptide for its binding site on human gamma glutamyl carboxylase. We attributed this to an increased turnover rate. However, even with the reduced affinity propeptide, when sufficient overproduction of factor X is achieved, there is still a significant fraction of uncarboxylate...